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To solve the decrease in the crystallization, mechanical and thermal properties of recycled polyethylene terephthalate (rPET) during mechanical recycling, the aromatic amide fatty acid salt nucleating agents Na-4-ClBeAmBe, Na-4-ClBeAmGl and Na-4-ClAcAmBe were synthesized and the rPET/nucleating agent blend was prepared by melting blending. The molecular structure, the thermal stability, the microstructure and the crystal structure of the nucleating agent were characterized in detail. The differential scanning calorimetry (DSC) result indicated that the addition of the nucleating agent improved the crystallization temperature and accelerated the crystallization rate of the rPET. The nucleation efficiencies (NE) of the Na-4-ClBeAmBe, Na-4-ClBeAmGl and Na-4-ClAcAmBe were increased by 87.2%, 87.3% and 41.7% compared with rPET which indicated that Na-4-ClBeAmBe and Na-4-ClBeAmGl, with their long-strip microstructures, were more conducive to promoting the nucleation of rPET. The equilibrium melting points (T 0 m) of rPET/Na-4-ClBeAmBe, rPET/Na-4- ClBeAmGl and rPET/Na-4-ClAcAmBe were increased by 11.7 ◦C, 18.6 ◦C and 1.9 ◦C compared with rPET, which illustrated that the lower mismatch rate between rPET and Na-4-ClBeAmGl (0.8% in b-axis) caused Na-4-ClBeAmGl to be the most capable in inducing the epitaxial crystallization and orient growth along the b-axis direction of the rPET. The small angle X-ray diffraction (SAXS) result proved this conclusion. Meanwhile, the addition of Na-4-ClBeAmGl caused the clearest increase in the rPET of its flexural strength and heat-distortion temperature (HDT) at 20.4% and 46.7%. [ABSTRACT FROM AUTHOR]

The 50 Li 2 O - x Al 2 O 3 - (50 - x) B 2 O 3 (x = 3–7 mol%) glass-ceramics were prepared by solid-state reaction method. Homogeneous glasses were obtained by water quenching, and the glass-ceramics with the LiBO 2 and Li 3 AlB 2 O 6 as main crystalline phases were prepared after the subsequent sintering process. The appropriate content of Al 2 O 3 can significantly improve the densification and crystallization of Li 2 O - Al 2 O 3 – B 2 O 3 (LAB) glasses. The fully densified glass-ceramics with 4 mol% Al 2 O 3 exhibit uniform and fine microstructure and large volume density. This glass-ceramic sintered at 650 °C for 7 h displays excellent microwave dielectric properties with ε r = 5.47, Q × f = 21814 GHz (at 13.6 GHz), and τ f = - 61.3 ppm/°C. Additionally, the LAB glass-ceramics are chemically compatible with aluminum (Al) and silver (Ag) electrodes at their sintering temperatures, which shows significant potential in ultralow temperature co-fired ceramic (ULTCC) for packaging substrate applications based on their good microwave dielectric performance and good chemical compatibility. [ABSTRACT FROM AUTHOR]

Blending octene random copolymer (ORC) with other polymers is a promising approach to improving ORC mechanical properties, such as tensile strength and elongation. In this study, octene block copolymer (OBC) with lower density than ORC and high-density polyethylene (HDPE) were used to blend with ORC. The effect of both OBC and HDPE on ORC was analyzed using scanning electron microscopy (SEM), differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA) and small-angle X-ray scattering (SAXS). For ORC/OBC blends, a small amount of OBC can improve the crystallization ability of ORC. Meanwhile, for ORC/HDPE blends, the crystallization ability of ORC was significantly suppressed, attributed to good compatibility between ORC and HDPE as indicated by the homogeneous morphology and the disappearance of the α transition peak of ORC in ORC/HDPE blends. Therefore, the tensile strength and elongation of ORC/HDPE blends are significantly higher than those of ORC/OBC blends. For ORC/OBC/HDPE ternary blends, we found that when ORC:OBC:HDPE are at a ratio of 70:15:15, cocrystallization is achieved. Although HDPE improves the compatibility of ORC and OBC, the three-phase structure of the ternary blends can be observed through SAXS when HDPE and OBC exceed 30 wt%. Blending HDPE and OBC (≤30 wt%) could improve the mechanical property of ORC. [ABSTRACT FROM AUTHOR]

x ZnO- (100- x) B 2 O 3 (x = 45–64 mol%) glass-ceramics for ULTCC applications were prepared via the solid-state reaction method, and their crystallization behavior, sintering mechanism, microstructure and microwave dielectric properties were investigated. In this work, the zinc boron binary glasses can be formed in the range of 45–73 mol% ZnO content, and the glass with 55 mol% ZnO content has the highest glass-forming ability. The Zn 4 B 6 O 13 crystal is formed in binary ZnO-B 2 O 3 glass at 640 °C, which is much lower than that in ceramics. The glass-ceramics exhibit large grains with 5 ∼ 10 µm consisting of fine and uniform secondary structures. The precipitation of Zn 4 B 6 O 13 crystal and the refinement secondary structure improves the microwave dielectric properties. The 55 ZnO - 45 B 2 O 3 glass-ceramic sintered at 640 °C for 5 h exhibits the optimum microwave dielectric properties of ε r = 6.09, Q×f = 20,389 GHz, τ f = 14 ppm/°C, and also high Vickers hardness of 625 kgf/mm2 and good chemical compatibility with Ag or Al electrode, which is a good candidate for ULTCC substrate materials. [ABSTRACT FROM AUTHOR]

为探究硬脂烷醇（SA）和米糠蜡（RW）在油凝胶中的相互作用机制，以不同配比的SA和RW为凝胶剂制备了葵花籽油凝胶，采用差示扫描量热仪（DSC）、低场核磁共振仪和偏光显微镜（PLM）探究不同SA与RW配比对油凝胶热性质、微观结构形态和结晶行为的影响。结果发现：不同油凝胶的固体脂肪含量（SFC）随温度的升高出现二次降低现象；随着SA和RW配比的变化，SA和RW在体系中按熔点高低顺序结晶，在结晶过程中出现共晶现象；RW油凝胶的晶体为棒状或针状结构，SA油凝胶的晶体为片状结构，当SA在凝胶剂中占比增加时，晶体聚集体形态由针状或棒状晶体聚集物转变为针状晶体夹杂小片状晶体的聚集物，再转变为片状晶体夹杂细小针状晶体的聚集物；在20 ℃下，当SA与RW质量比为1∶ 9、3∶ 7、5∶ 5和7∶ 3时，油凝胶呈现两步结晶现象，SA与RW质量比为0∶ 10、9∶ 1和10∶ 0时油凝胶呈现一步结晶现象；30 ℃下，SA与RW质量比为7∶ 3时油凝胶呈现两步结晶现象，其余油凝胶呈现一步结晶现象。综上，不同配比的SA和RW对油凝胶的影响主要体现在SFC的熔化趋势变化、热性质差异、晶体形态变化和结晶行为的差异上，这些变化是由于在微观结构上两种凝胶剂晶体粒子之间相互作用导致的。 In order to investigate the interaction mechanism of stearyl alcohol (SA) and rice bran wax (RW) in oleogels, sunflower seed oil oleogels were prepared by the mixture of SA and RW with various ratios as gelators. The effects of the ratio of RW to SA on the thermal properties, microstructure and morphology, and crystallization behavior of these oleogels were investigated by differential scanning calorimeter (DSC), low field nuclear magnetic resonance and polarizing microscope (PLM). The results showed that the solid fat contents(SFC) of different oleogels showed two-step decrease with temperature increasing. As the content of SA increased, RW and SA melted and crystalized sequentially. The cocrystal behavior appeared in the crystallization of the binary oleogels. The crystal morphology of RW oleogel was needle-like or rod-like structure, that of SA oleogel was plate-like. With decrease of the ratio of RW to SA, the morphology of the oleogels changed from the aggregates of needle-like or rod-like crystal to aggregates of needle-like crystals entrapped with small plate crystals, to aggregates of large plate crystals entrapped with small needle-like crystals. The oleogels formed by the gelators with the mass ratio of SA to RW 1∶ 9, 3∶ 7, 5∶ 5 and 7∶ 3 presented two-step crystallization, others showed one-step crystallization at 20 ℃. The oleogels formed by the gelators with the mass ratio of SA to RW 7∶ 3 showed two-step crystallization, and the others indicated one-step crystallization at 30 ℃. In conclusion, the influence of different ratios of SA to RW in oleogels showes variety of SFC melting process, thermal properties differences, variety of crystal morphology and different crystallization behavior, which are caused by the interaction of SA and RW crystals particles in the microstructure.

Copyright of China Plastics / Zhongguo Suliao is the property of Journal Office of CHINA PLASTICS and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Blending octene random copolymer (ORC) with other polymers is a promising approach to improving ORC mechanical properties, such as tensile strength and elongation. In this study, octene block copolymer (OBC) with lower density than ORC and high-density polyethylene (HDPE) were used to blend with ORC. The effect of both OBC and HDPE on ORC was analyzed using scanning electron microscopy (SEM), differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA) and small-angle X-ray scattering (SAXS). For ORC/OBC blends, a small amount of OBC can improve the crystallization ability of ORC. Meanwhile, for ORC/HDPE blends, the crystallization ability of ORC was significantly suppressed, attributed to good compatibility between ORC and HDPE as indicated by the homogeneous morphology and the disappearance of the α transition peak of ORC in ORC/HDPE blends. Therefore, the tensile strength and elongation of ORC/HDPE blends are significantly higher than those of ORC/OBC blends. For ORC/OBC/HDPE ternary blends, we found that when ORC:OBC:HDPE are at a ratio of 70:15:15, cocrystallization is achieved. Although HDPE improves the compatibility of ORC and OBC, the three-phase structure of the ternary blends can be observed through SAXS when HDPE and OBC exceed 30 wt%. Blending HDPE and OBC (≤30 wt%) could improve the mechanical property of ORC.

In this study, nanostructural TiCN coatings were prepared by reactive plasma spraying micrometer Ti/graphite powders under atmospheric conditions, and the crystallzation behaviors and mechanical properties of as-sprayed coatings were discussed. The results showed that the mechanical properties of as-sprayed coatings depend mainly on the crystallization behavior and resultant morphology of the structure. The sprayed coatings were mainly composed of fully, partically and unmelted particles, which exhibit different crystallization characteristics. Overall, the sprayed coating mainly consisted of columnar grains accompanied by few equixaed grains, and the size of these grains are about 50–100 nm in diameter. In parallel to the substrate/coatings surface direction, columnar grains or columnar dendrites were observed at the partially/unmelted particles and edage of particles. However, in vertical to the substrate surface direction, the coatings were mainly composed of columnar grains accompanied by few equiaxed grains. These different crystallzation behaviors of surface and cross-section resulted in different properties. Especially, the tight columnar grains in cross-sections with multi-long-diameter ratios presented better deformation resistance than that of the surface. Besides, during the coating deposition process, some pores were retained in the coating as 'close pores' and thus the compactness of the cross-sections was higher than that of the surface. In this case, the micro-hardness and indentation toughness on the cross-sections were better than those of the coatings surfaces. [ABSTRACT FROM AUTHOR]

Copyright of Plastics Science & Technology / Suliao Ke-Ji is the property of Plastics Science & Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Rare Metals is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this work, the effects of annealing temperatures and time on the microstructure and soft magnetic properties of (Fe 0.83 B 0.11 Si 0.02 P 0.03 C 0.01) 99.5 Cu 0.5 nanocrystalline alloy were investigated using a new rapid annealing process. The results show that at each annealing temperature, there exists an annealing time for optimum soft magnetic properties. The annealing temperature and time were further optimized, and excellent properties with high saturation magnetic induction B s of 1.79 T and low coercivity H c of 2.7 A/m were obtained by annealing at 431 °C for 150 s. A microstructure consisting of uniform and fine α-Fe(Si) grains with high number density and high crystallization volume fraction was found to be the key to ensure high B s and low H c. However, with increasing annealing time, it was found that α-Fe(Si) grains existed aggregation phenomenon (in the form of high-angle grain boundaries), with the simultaneous precipitation of Fe-B compound precipitated in the residual amorphous matrix. This not only causes the uneven distribution of nanocrystals, but also destroys the competitive effect between nanocrystals and the stability of the structure, thus deteriorating the soft magnetic properties. [ABSTRACT FROM AUTHOR]

Various glass-ceramics were prepared based on the CaO-Al 2 O 3 -SiO 2 system with the addition of Li 2 O in an attempt to develop a suitable sealant for SiC ceramic. The effects of Li 2 O content on crystallization behavior and thermal expansion properties were systematically investigated. The results revealed that the addition of Li 2 O significantly reduced the crystallization activation energy of glass. Besides, as the Li 2 O content increased, the precipitation of spodumene and wollastonite was promoted while the precipitation of anorthite was suppressed. By controlling the Li 2 O content and crystallization treatment, the coefficient of thermal expansion (CTE) of glass-ceramic could be adjusted in a certain range, from 8.5 × 10−6/°C to 2.8 × 10−6/°C. When the content of Li 2 O was 3 wt.%, the CTE of the formed glass-ceramic was well-matched with that of SiC ceramic. Furthermore, it was confirmed that this glass-ceramic possessed an excellent wettability and weldability to SiC ceramic. [ABSTRACT FROM AUTHOR]

Glass microspheres are considered to be suitable fillers in syntactic foams due to their high specific strength, however, it's evidently easy to react with Al-Mg alloy or Mg alloy. A surface protection coating MgO were successfully prepared on microspheres using sol-gel method. The crystallization process and coating effect of MgO with different molar ratio acetic acid complexant in sol compositions were studied. The dried gels were dehydrated and polycondensed to form magnesium acetate and finally turned to be stable MgO after annealing at 400 °C. The MgO coatings, with small particles after annealing, successfully modified the surface of microspheres when the sol composition (molar) magnesium acetate hydrate/acetic acid/dry ethanol was 1:6:29. The MgO coating has inhibited the excessive interfacial reaction between the glass microspheres and the Al-Mg alloy matrix in syntactic foam which the reasons have been discussed. • Glass microspheres were modified with MgO coating using sol-gel method. • The crystallization of coating was gel to magnesium acetate and finally to crystals. • The morphology evolution of coating was island-shaped gel to MgO fine particles. • The coating effect of MgO can be tailored by the complexant acetic acid in sols. • MgO coating can inhibit the interfacial reaction in glass microspheres/Al-Mg foam. [ABSTRACT FROM AUTHOR]

In the present study, the extensive efforts had been made to attain the higher-quality Zr Cu based ribbons by optimizing the fabrication process. Under the same preparation conditions, the as-spun Zr Cu based ribbons with the different amorphous state can be obtained by tailoring the chemical compositions. The microstructure of the as-spun Zr 50 Cu 50 ribbon was featured with the amorphous matrix embedded with the B2 crystalline and the superior mechanical properties can be achieved as a result of the martensitic transformation induced by stress during deformation. The partial substitute of Cu by Ni and Co enhanced the ability of forming the amorphous Zr-Cu-Ni-Co ribbons and the size of the B2 crystalline gradually became smaller. The reduction of B2 crystalline in the amorphous matrix led to the slight decrease in the mechanical properties of the as-spun Zr Cu based ribbons. However, the microstructure of the annealed Zr Cu based ribbons was characterized by the nano-scale grain. Meanwhile, the nano-scale Cu 10 Zr 7 precipitates distributed in the nanograin. The grain refinement and precipitation strengthening contributed to the superior mechanical properties of the annealed Zr Cu based ribbons. • The higher quality Zr Cu based ribbons were successfully prepared. • The amorphous degree can be tailored by composition in Zr Cu based ribbons. • The microstructure of annealed Zr Cu based ribbons was featured with nano-grains. • The phase constitutions of annealed Zr Cu based ribbons were dependent on composition. • The as-spun and annealed Zr Cu based ribbons showed superior mechanical properties. [ABSTRACT FROM AUTHOR]

Abstract B 2 O 3 -containing MgO-Al 2 O 3 -SiO 2 -Li 2 O glass-ceramics were fabricated via crystallization treatment of primal glasses for the purpose of joining Si 3 N 4 ceramics. The effects of B 2 O 3 content on the crystallization behavior, coefficient of thermal expansion and softening temperature of MgO-Al 2 O 3 -SiO 2 -Li 2 O-B 2 O 3 glasses were investigated. The results reveal that the glass transition temperature and the crystallization temperature of the glasses decrease with the increasing B 2 O 3 content. It also demonstrates that γ-spodumene solid solution is detected in the glass-ceramics after heat treatment at 735 °C and 840 °C, respectively, whereas the heat treatment at 1000 °C results in the precipitation of β/γ-spodumene coexisting phases solid solution and forsterite. Additionally, by controlling the composition and crystallization treatment, the CTEs of glass-ceramics can be matched with the Si 3 N 4. Furthermore, contact angle measurement confirms that the glass-ceramics possess a good wettability on the Si 3 N 4 substrate, which can be considered as the candidate materials for joining Si 3 N 4 ceramics. [ABSTRACT FROM AUTHOR]

Polyphenylene sulfide (PPS)/multiwalled carbon nanotube (MWCNT) composites were prepared by melt blending and injection molding. The nonisothermal crystallization behavior, morphology, and mechanical properties of the nanocomposites were systematically investigated as a function of MWCNT content. For nonisothermal process, the presence of MWCNTs possesses both acceleration and retardation effect on the crystallization of PPS without affecting the ultimate degree of crystallinity. Due to the interfacial interaction between MWCNTs and PPS, the MWCNTs can be uniformly dispersed in PPS. The interfacial crystallization of PPS on the surface of nanotubes was observed by scanning electron microscopy and transmission electron microscopy. A reinforcing effect of MWCNTs on the mechanical properties of PPS is found, which is considered to be relevant with the uniformly dispersed MWCNTs and the interfacial crystallization. [ABSTRACT FROM AUTHOR]

The substitution for Nd by abundant element cerium (Ce) is a practical way for the comprehensive utilization of rare earth resources in NdFeB permanent magnets. In this letter, we have prepared the Ce-doped NdFeB ribbons and conventional NdFeB ribbons by melt quenching method and investigated the effects of heat treatment on the crystallization behavior, microstructure, and magnetic properties of the alloy. The results show that: (1) The crystallization behavior and the microstructural changes of the (Nd,Ce)FeB magnets are similar to the conventional NdFeB magnet when heat treatment. In addition, the Ce2Fe14B phase has a significant effect on the properties of the whole magnets. (2)The NdFeB phase and CeFeB phase are relatively close to each other after being precipitated from the amorphous phase. The coupling effect between the two phases is strong enough to weaken the effect of the addition of Ce and making the properties of the NdFeB magnets to not reduce too much after adding Ce. [ABSTRACT FROM AUTHOR]

PKO and CNO are composed of 97–98% triacylglycerols and 2–3% minor non-triglyceride components (FFA, DAG and MAG). Triglycerides were separated from minor components by chromatographic method. The lipid composition, thermal properties, polymorphism, isothermal crystallization behavior, nanostructure and microstructure of PKO, PKO-TAG, CNO and CNO-TAG were evaluated. Removal of minor components had no effect on lipid composition and equilibrium solid fat contents. However, presence of minor components did increase the slip melting point and promoted the onset of crystallization from DSC crystallization profiles. The thickness of the nanoscale crystals increased with no polymorphic transformation after removing the minor components. Crystallization kinetics revealed that minor components decreased crystal growth rate with higher t 1/2 . Sharp changes in the values of the Avrami constant k and exponent n were observed for all fats around 10 °C. Increases in n around 10 °C indicated a change from one-dimensional to multi-dimensional growth . From the results of polarized light micrographs, the transformation from the coarser crystal structure to tiny crystal structure occurred in microstructure networks at the action of minor components. [ABSTRACT FROM AUTHOR]

The glass transition phenomenon for Zr 65 Al 7.5 Ni 10 Cu 17.5-x Ag x (x = 5–17.5 at%) glassy alloys was observed in the Ag content range below about 15% and the icosahedral phase precipitated as the heating-induced primary phase in the limited Ag content range. In the higher Ag content range where glass transition is not clearly observed, the primary precipitation phase changed to mixed phases of tetragonal Zr 3 Ag + tetragonal Zr 2 Ni + hexagonal Zr 4 Al 3 . The good correspondence between the appearance of glass transition and the icosahedral phase precipitation was recognized in the multicomponent glassy alloys containing the immiscible type atomic pairs of Ni-Ag and Cu-Ag. Although neither glass transition nor supercooled liquid region is observed for Zr 65 Al 7.5 Ni 10 Ag 17.5 and no icosahedral phase is formed, a modified Zr 65 Al 7.5 Ni 17.5 Ag 10 alloy with higher Ni/Ag content ratio exhibits glass transition and supercooled liquid region and the primary precipitates also changes to an icosahedral phase. The good correspondence can be interpreted on the basis of the previous knowledge that the appearance of glass transition and supercooled liquid state originates from icosahedral-like medium range ordered atomic configurations. Besides, the 6%Ag-containing alloy keeps high glass-forming ability which is high enough to form a bulk glassy alloy rod of 6 mm by suction casting. The close correlation between the appearance of glass transition phenomenon and the primary precipitation of icosahedral phase is expected to provide a useful knowledge on the role of icosahedral-like atomic configuration in the achievement of bulk glass-forming ability through the stabilization of supercooled liquid. [ABSTRACT FROM AUTHOR]

The effects of Cu addition on the crystallization behavior and microstructure of melt-spun ribbons have been studied. XRD shows that Cu addition promotes the crystallization. DSC shows that Cu addition can change the crystallization behavior of (NdPr)(FeNbCo)(BC) from a two-step to a single-step process. Three-dimensional atom probe (3DAP) results show the formation of a high-number density of Cu clusters in higher Cu addition, while Cu clusters were not found in the alloy of lower Cu addition. [ABSTRACT FROM AUTHOR]

To understand the role of molecular structure on the crystallization behavior of copolyester in thermoplastic poly(ether ester) elastomers (TPEEs), series of poly(butylene-co-1,4-cyclohexanedimethylene terephthalate) (P(BT-co-CT))-b-poly(tetramethylene glycol) (PTMG) are synthesized through molten polycondensation process. The effects of poly(cyclohexanedimethylene terephthalate) (PCT) content on the copolymer are investigated by Fourier transform infrared spectroscopy (FT-IR), ¹H and 13C nuclear magnetic resonance (NMR), gel permeation chromatographs (GPC), wide-angle X-ray diffraction (WAXD), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), mechanical, and visible light transmittance tests. FT-IR and NMR results confirm the incorporation of PCT onto the copolymer. WAXD and DSC indicate that the crystalline structure of the copolymers changed from α-PBT lattice to trans-PCT lattice when the molar fraction of PCT (MPCT) is above 30%, while both crystallization and melting temperatures reach the minima. An increase in MPCT led to an increase in the number sequence length of PCT, the thermal stability and the visible light transmittance of the copolymer, but to a slight decrease in tensile strength and elastic modulus. [ABSTRACT FROM AUTHOR]

The method of selective laser melting (SLM) is a new manufacturing technology which has been regarded as a potential candidate to prepare bulk metallic glasses (BMGs) without limit of critical dimensions. However, obstacles still remain since the crystallization is rather hard to be sustained in the heat affected zone (HAZ) during the preparation of BMGs, due to the existence of cyclic heating process. In order to find the possibility of inhibiting the crystallization behavior in the HAZ, the micro-structural evolution of Ni 75 Al 25 metallic glass during the cyclic heating process at different temperature variation rates was studied with Molecular Dynamics (MD) simulation. The results reveal that at low temperature variation rates relatively, the crystallization begins during the heating or cooling process depends on the relaxation time between the glass transition temperature T G and the maximum heating temperature T MAX . The relaxation time also affects the transformation mode of crystal structure after the completion of crystallization behavior. When the temperature variation rate rises to 5 × 10 13 K/s, the decline of nucleation occurred: during the heating process, the heating rate is so high that the nuclei at the low temperature could come into the embryo at the high temperature which lead to the fusion of crystal embryos. And the decline of nucleation provides a new possibility for the research on the inhibition of crystallization behavior in the HAZ during the preparation of BMGs with SLM. [ABSTRACT FROM AUTHOR]

• Granite wastes were used to prepared glass-ceramics to make good use of wastes. • Successfully generated multiphase glass-ceramics containing diopside and mica. • The effects of SiO 2 /MgO molar ratios of glass-ceramics were investigated. • There were excellent mechanical properties for mica-diopside based glass-ceramics. Mica-Diopside based glass-ceramics were generated by melting method from granite wastes. The effects of SiO 2 /MgO (S/M) molar ratios on crystallization behavior, microstructure and mechanical characteristics of glass-ceramics were investigated. The analysis indicated that with the increase of S/M, the glass transition temperature (T g) increased. The higher heat treatment temperature facilitated the formation of Forsterite than Nepheline. With S/M ratio rising, diopside turned into the main crystal phase instead of Forsterite along with Tainiolite as the minor phase at 850 °C and 900 °C respectively. At 900 °C, the crystallinity of glass-ceramics dropped with S/M ratio increasing. Meanwhile, there were some columnar crystals interleaving with granular crystals, and the average size of crystals obviously decreased. After heated at 900 °C, their Vickers-hardness fell dramatically with S/M rising, while the fracture toughness increased initially followed by a decrease, reaching the largest value of 1.97 MPa·m1/2 with the S/M ratio of 2.82. [ABSTRACT FROM AUTHOR]

In the Zr 41.2 Ti 13.8 Cu 12.5 Ni 10 Be 22.5 (Vit1) alloy undergoing high temperature deformation, its thermal properties and microstructure are quite different from those in the annealing alloy. In order to research the coupled effect of temperature and plastic strain on microstructural evolution of Zr-based amorphous, uniaxial compression test of Vit1 alloy with good amorphous nature has been performed, and then the structural state and thermal properties of Vit1 alloy after thermal deformation and isothermal annealing in the supercooled liquid region were investigated. It is revealed that the deformed specimens possess higher characteristic temperature and lower enthalpy change of microstructural relaxation. In addition, the smaller inter-atomic distance and higher order degree of atomic arrangement can be observed in those deformed Vit1 alloy. That can be deduced that thermal deformation is in favor of the microstructural evolution from a metastable amorphous state to stable crystallization state, because plastic strain promotes the annihilation of free volume and provide excess driving force of atomic diffusion. However, upon increasing the ambient temperature, the influence of plastic deformation on microstructure gradually decreased owing to the decreasing proportion of the plastic deformation-induced annihilation of free volume during the whole thermal deformation process. [ABSTRACT FROM AUTHOR]

To elucidate the possible interaction mechanisms between DAG-enriched oils, this study investigated how mixtures of DAG-enriched palm-based oils influenced the phase behavior, thermal properties, crystallization behaviors and the microstructure in binary fat blends. DAG-enriched palm oil (PO-DAGE) was blended with DAG-enriched palm olein (POL-DAGE) in various percentages (0%, 10%, 30%, 50%, 70%, 90%, 100%). Based on the observation of iso-solid diagram and phase diagram, the binary mixture of PO-DAGE/POL-DAGE showed a better compatibility in comparison with their corresponding original blends. DSC thermal profiles exhibited that the melting and crystallization properties of PO-DAGE/POL-DAGE were distinctively different from corresponding original blends. Crystallization kinetics revealed that PO-DAGE/POL-DAGE blends displayed a rather high crystallization rate and exhibited no spherulitic crystal growth. From the results of polarized light micrographs, PO-DAGE/POL-DAGE blends showed more dense structure with very small needle-like crystals than PO/POL. X-ray diffraction evaluation revealed when POL-DAGE was added in high contents to PO-DAGE, above 30%, β -polymorph dominated, and the mount of β ′ forms crystals was decreasing. [ABSTRACT FROM AUTHOR]

Polypropylene (PP) blended with eucommia ul moides gum (EUG) has been investigated in this work. The mechanical properties, processing properties, crystallinity and microstructure of different blends were researched to find the best mixed ratio of EUG in the blend. The results showed that the impact strength of PP blended with 25 % mass fraction of EUG was improved as much as twice and the properties of material were transferred from brittleness to ductility. The survey of DSC indicated that degree of crystallinity ( X) of the blend was first promoted and later inhibited with the mass fraction of EUG increasing, when the weight percent ratio of EUG was 10 %, the value of X got to the maximum of 30.35 %. Polarizing microscopes exhibited that the addition of EUG could promote the spherulite refinement and increase significantly amorphous areas of PP. Morphology of fracture surfaces observed by SEM demonstrated that the brittle fracture of pure PP material transformed to the ductile fracture with increasing EUG and then the toughening mechanisms were discussed. [ABSTRACT FROM AUTHOR]

A series of terpolymers with various compositions were synthesized by ring-opening polymerization of l -lactide (LLA), trimethylene carbonate (TMC) and glycolide (GA), using stannous (II) octoate as initiator. The microstructure–property relationship of the terpolymers was investigated with the aim of evaluating their potential as cardiovascular stent material. The chain microstructure of the PLLA–TMC–GA terpolymers was examined by means of both 1 H and 13 C nuclear magnetic resonance (NMR) analysis, in comparison with corresponding PLLA–TMC copolymers. The results show that the incorporation of GA moiety instead of TMC moiety leads to shorter average LLA block length. Differential scanning calorimetry (DSC) results show a close relationship between the crystallization behavior and the microstructural sequence. The crystallinity of PLLA-based copolymers mainly depends on the average LLA block length. The mechanical and thermal degradation properties are also affected by both the composition and the chain microstructure, which is of major importance for the development of bioresorbable cardiovascular stent. [ABSTRACT FROM AUTHOR]

Abstract: (Nd0.4Pr0.6)9Fe76−x Nb x B15 (x=0–5) flakes were fabricated by slow quenching from master alloys. Effects of Nb on crystallization behavior and magnetic properties of flakes have been systematically investigated. For the sample with x=0, the metastable compound (Nd,Pr)2Fe23B3 crystallized as a precursor from amorphous state and then transformated to the (Nd,Pr)2Fe14B and α-Fe phases, and the (Nd,Pr)1.1Fe4B4 phase was formed on further increasing annealing temperature to 700°C. So the crystallization process of the (Nd0.4Pr0.6)9Fe76B15 alloy was as follows: amorphous phase (AP)→AP′+(Nd,Pr)2Fe23B3→(Nd,Pr)2Fe14B+α-Fe→(Nd,Pr)2Fe14B+α-Fe+(Nd,Pr)1.1Fe4B4. For the sample with x=4, the α-Fe phase was first formed from amorphous matrix, and then the (Nd,Pr)2Fe14B and Fe3B phases subsequently crystallized from residual amorphous phase. So the crystallization process of the (Nd0.4Pr0.6)9Fe72Nb4B15 alloy was as follows: amorphous phase (AP)→α-Fe+AP′ →α-Fe+Fe3B+(Nd,Pr)2Fe14B. The addition of Nb to (Nd0.4Pr0.6)9Fe76B15 alloy could suppress the formation of the metastable (Nd,Pr)2Fe23B3 phase and nonmagnetic (Nd,Pr)1.1Fe4B4 phase. Meanwhile, microstructure of (Nd0.4Pr0.6)9Fe76B15 flakes was significantly refined by introducing Nb. After optimal annealing treatment, the intrinsic coercivity increased from 397.3kA/m for the Nb-free sample to 1297kA/m for the 5at% Nb-doped sample. [Copyright &y& Elsevier]

Impact polypropylene copolymer (IPC), named polypropylene catalloy, not only possesses excellent impact property, but also presents good rigidity. Its superior performances result from the complicated composition and microstructure. In the present article, recent progress in the studies on microstructure, morphology, crystallization and rheological behavior of IPC is summarized, and findings of the authors and their collaborators are reported. In general, IPC is divided into three components, i.e., ethylene-propylene random copolymer (EPR), a series of different segment lengths ethylene-propylene copolymer (E bP) and propylene homopolymer. The reasonable macromolecular structures of E bP and a multilayered core-shell model of dispersed phase structure in IPC were proposed, in which the dispersed phase consists of an outer E bP shell, an inner EPR layer and an E bP core. It is found that the annealing at melt-state may lead to an abnormal phase inversion, and the phase inversion disappears when temperature cools down to room temperature. The cause of phase inversion is ascribed to the existence of E bP component, which results in the stronger activity of the dispersed phase. The crystalline structure and morphologic results confirm the formation of β- iPP in IPC. Furthermore, it is found that the ethylene content in IPC and cooling rate of the samples have an important influence on the formation of β- iPP. Based on the crystallization kinetics analyzed by Lauritzen-Hoffman theory, crystallization behavior of different IPC samples is discussed and it is proposed that the dilution effect of ethylene-propylene copolymer has a more remarkable influence on surface nucleation than on crystal growth. In addition, annealing at high temperature can result in the changes of chain structure for IPC, and this instability is ascribed to the oxidative degradation and crosslink reaction mainly in iPP component. [ABSTRACT FROM AUTHOR]

Abstract: Characterization of B2O3 and/or WO3 containing tellurite glasses was realized in the 0.80TeO2–(0.20− x)WO3 − xB2O3 system (0≤ x ≤0.20 in molar ratio) by using differential scanning calorimetry, Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy and energy dispersive X-ray spectrometry techniques. Glasses were prepared with a conventional melt-quenching technique at 750°C. To recognize the thermal behavior of the glasses, glass transition and crystallization temperatures, glass stability value, glass transition activation energy, fragility parameter were calculated from the thermal analyses. Density, molar volume, oxygen molar volume and oxygen packing density values were determined to investigate the physical properties of glasses. Fourier transform infrared spectra were interpreted in terms of the structural transformations on the glass network, according to the changing B2O3 and/or WO3 content. Crystallization behavior of the glasses was investigated by in situ X-ray diffraction measurements and microstructural characterization was realized by scanning electron microscopy and energy dispersive X-ray spectrometry analyses. [Copyright &y& Elsevier]

Abstract: Fe75Co6Zr9B10 amorphous alloy prepared by melt-spinning was annealed at various temperatures. The crystallization behavior and microstructure were investigated by differential thermal analysis (DTA), X-ray diffraction (XRD), transmission electron microscopy (TEM) and atomic force microscopy (AFM). The three exothermal peaks in the DTA curve of Fe75Co6Zr9B10 amorphous alloy correspond to the formations of α-Fe and α-Mn type phases, the growth of BCC-Fe volume fraction at the expense of α-Mn and residual amorphous phase and the precipitations of Fe3Zr, etc. intermetallic compounds, respectively. The second exothermic peak is not influenced by heating rate, but it shifts to a higher temperature region with increasing preannealing temperature of Fe75Co6Zr9B10 alloy. The α-Mn type phase is metastable and its lattice parameter determined by TEM is 0.8830nm. AFM images show the development of surface morphology of alloy after annealing. The particle size increases with increasing annealing temperature. [Copyright &y& Elsevier]

To manufacture beef tallow (BT)-based shortening and margarine with a reduced tendency to developing sandiness, BT/canola oil (CaO) blend (80:20 w/w), selected from the BT and CaO blends mixed in different ratios from 60:40 to 85:15 with 5% increments, was subjected to chemical interesterification (CIE) with sodium methoxide as the catalyst. The interesterified products were compared with the starting mixture in terms of solid fat content (SFC), and contents of high-melting point 1,3-disaturated long-chain fatty acid 2-monounsaturated long-chain fatty acid triacylglycerols (SUS TAGs) including 1,3-distearoyl-2-oleoyl-glycerol (StOSt), 1,3-dipalmitoy-2-oleoyl-glycerol (POP), and 1-palmitoyl-2-oleoyl-3-stearoyl-glycerol (POSt). Under the selected conditions: 60 °C, 0.6% CHONa, 90 min, the CIE product had a SFC profile that meets suggested bakery fat requirements, besides a content of SUS TAGs which is 22.14% lower than that of the non-interesterified blend. Also the fat produced had stable β′ polymorphs, crystal morphology, crystal sizes (<20 μm), and could resist temperature fluctuations. The CIE product obtained herein has an increased potential for manufacturing bakery shortenings and margarines with reduced graininess formation, increasing the possibilities for the commercial use of BT and CaO. [ABSTRACT FROM AUTHOR]

Abstract: The latent heats of fusion ΔH ms of Co–Si alloys over a wide range of composition have been determined. Based on the measured data, the dimensionless entropy (α =ΔH m/T l R, T l is liquid temperature and R is gas constant) was calculated and the crystallization behaviors, faceted or non-faceted crystal growth, of several intermetallic compounds were predicted and examined by experiments. ΔH m increases with the Si content. However, the values are lower than those obtained via Neumman–Kopp rule with linear extrapolation. The α coefficients calculated by the experimental data reveal that the Co2Si, CoSi, and CoSi2, should grow in a non-faceted manner and it was proved by the microstructure observation after solidification. For α value determined by the Neumman–Kopp rule, Co–Si intermetallic compounds should be faceted morphology, indicating that their ΔH m should be measured experimentally. [Copyright &y& Elsevier]

Abstract: The influence of crystallization on the corrosion resistance of bulk metallic glass Fe66.7C7.0Si3.3B5.5P8.7Cr2.3Al2.0Mo4.5 fabricated using industrial raw materials has been studied in the solutions of 0.5M H2SO4 and 1N HCl, respectively. It was found that corrosion resistance is strongly dependent on the microstructural change caused by annealing treatment. As-cast rods comprising fully amorphous phase exhibit higher corrosion resistance than crystallized rods. [Copyright &y& Elsevier]

Ni–P and Ni–P–Cr alloy coatings were deposited onto silicon substrates by the RF magnetron sputtering technique with dual targets of electroless nickel–phosphorus alloy and chromium. To evaluate the effect of doping with a third element on the enhancement of thermal stability in Ni–P coatings, differential scanning calorimetry (DSC) was used to identify the onset temperature of phase transformation. The crystallization behavior at different stages of phase transition in the DSC plot was further evidenced by X-ray diffraction (XRD). Microstructural evolution of the Ni–P based coating in the as-deposited and heat-treated states were investigated by transmission electron microscopy (TEM). The broad peak in the DSC plot of both Ni–P and Ni–P–Cr deposits is attributed to the grain coarsening of nickel on the basis of XRD and TEM analyses. The addition of Cr atoms into Ni–P based coating not only suppresses the formation of Ni3P but also reduces the grain size of precipitates. [Copyright &y& Elsevier]

Sapphirine glass ceramics were synthetized using small quantities of Cr2O3. The structure of the glass, transformation of the crystal phases, crystal growth behavior and physicochemical properties were investigated. Our results indicate that the content of Q3Si and Q4Al gradually decreased, while the content of Q2Si, Q1Si, and Q3Al increased within the parent glass during the addition of Cr2O3. The crystallization exothermic temperature of the parent glass decreased with addition of Cr2O3 and the main crystal phase of the resulting glass ceramic changed from α-cordierite to sapphirine. In Cr0 samples, square cordierite crystals of α-cordierite grew in the glass matrix. With Cr2O3 doped samples, pore-like (sapphirine-1A) and needle-like (sapphirine-2M) crystallographic morphology appeared. The addition of Cr2O3 was found to promote grain refinement of the sapphirine phase. Cr0.5 and Cr0.8 samples – with sapphirine as main crystal phase – can be used as medium thermal expansion material with a certain extent of strength and chemical resistance. In conclusion, the solid waste containing chromium can be used as raw material to prepare the sapphirine glass ceramics with a certain extent of strength, chemical resistance and thermal expansion coefficient. • Cr 2 O 3 was used as additive for preparing MgO–Al 2 O 3 –SiO 2 -(TiO 2) glass ceramics. • The structure of MgO–Al 2 O 3 –SiO 2 -(TiO 2) glass system and the transformation of main crystal phase were studied. • The microstructure and the crystallization behavior were observed. • Glass ceramics can be used as medium thermal expansion material with a certain extent of strength and chemical resistance. [ABSTRACT FROM AUTHOR]

• The Fe addition can promote the thermal stability of Ni-Fe-P alloys. • Ni-Fe-P coatings with three types of structure are all prepared. • The structure of these Ni-Fe-P coatings is mainly controlled by their iron content. • Amorphous coatings show the best wettability due to the high surface roughness. Thermal stability and wettability are important properties for under bump metalization (UBM) in electronic devices. This study aims at preparing the Ni-Fe-P coatings with varying microstructures and investigating the effects of microstructures on their properties including surface morphology, roughness, chemical bonding and wettability. The microstructure of the Ni-Fe-P coatings was mainly controlled by their Fe content. The crystallinity of these coatings continuously increased to 100% when the Fe content reached 12 wt.%, while they exhibited amorphous structure with a Fe content of below 9 wt.%. The wettability order of these coatings are amorphous, crystalline and mixed structure from the best to the worst, which is mainly due to their surface roughness. Moreover, the Fe addition in the Ni-P coatings can promote their thermal stability, showing a good potential as UBMs at elevated temperature. In a temperature range of 340°C – 480°C, the amorphous Ni-Fe-P coatings gradually transformed into Ni 3 P, FeNi 3 and slight Ni phases. [ABSTRACT FROM AUTHOR]

Phase separation and crystallization behavior in melt-spun Al 63 Si 25 Ni 12 amorphous alloy have been investigated in the present study. Although there is no atomic pair with positive enthalpy of mixing, nm scale phase separation occurs in the as-melt-spun amorphous alloy, exhibiting double-halo diffraction pattern. The amorphous matrix consisting of two different nm-scale Al-rich and Si-rich amorphous phases polymorphically crystallizes into a metastable hexagonal phase by an interface-controlled nucleation and growth mechanism in the first step of crystallization. The metastable hexagonal phase transforms into the mixture of α-Al, Si and Al 3 Ni phases possibly by a ternary eutectoid reaction in the second step of crystallization. Unlabelled Image • Phase separation occurs in as-melt-spun Al-Si-Ni amorphous alloy. • The amorphous matrix is separated into nm scale Al-rich and Si-rich regions. • The amorphous matrix crystallizes into single hexagonal phase. [ABSTRACT FROM AUTHOR]