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Al−high Si alloys were designed by the addition of Cu or Mg alloying elements to improve the mechanical properties. It is found that the addition of 1 wt.% Cu or 1 wt.% Mg as strengthening elements significantly improves the tensile strength by 27.2% and 24.5%, respectively. This phenomenon is attributed to the formation of uniformly dispersed fine particles (Al2Cu and Mg2Si secondary phases) in the Al matrix during hot press sintering of the rapidly solidified (gas atomization) powder. The thermal conductivity of the Al−50Si alloys is reduced with the addition of Cu or Mg, by only 7.3% and 6.8%, respectively. Therefore, the strength of the Al−50Si alloys is enhanced while maintaining their excellent thermo-physical properties by adding 1% Cu(Mg).

Both the Excess or under production rate disturbs the business cycle and increase the losses. Balanced business cycle is leads to healthy and ensured customer satisfaction and raise of sales volume. This paper discusses such industrial story in which the problem was excess cost incurred due to fast line delivery due to disturbed flow of products in the manufacturing line. This kind of issues usually carried out in two approaches like production management and production engineering. Based on the scientific analysis the production engineering approach was preferred. The flow process analysis carried out to locate the problem area. The ishikawa diagram plotted to identify the relationship between the factors, root cause analysis and validated the same. The Improved Design in tool with appropriate material is suggested for hot forming operation, fabricated and validated all the way to ensure its compatibility. The trails conducted for both conventional and proposed tools five days and performances measured. The improved performance guaranteed. Further the proposed tool validated with quality on its produced products like surface hardness of product, micro structural investigation on surface and core. The tool diaphragm validated by mechanic testing, cover assembly validation test and cost analysis. Cooling rate reduced 34.78%, cycle time reduction 24.24%, production rate augmented 30.91% per hour. The use of propane gas proposed than LPG to reduce the cost.

Dense boron carbide bearings with a central through hole were fabricated by hot-press sintering. When the sintering temperature was above the critical grain growth temperature, an increase in the applied pressure at 2100 °C caused a distinct abnormal grain size region. Two grain growth mechanisms were explored; normal grain growth (NGG) is controlled by a grain boundary diffusion mechanism whereas the abnormal grain growth (AGG) pattern abides by the ‘Bose–Einstein’ grain growth law.

In this study, a microwave hot press sintering (MHPS) strategy was developed for metal-bonded diamond composites (MBDC). The main focus was on the MHPS process of Fe60Cu40 pre-alloy bonded diamond composites. The temperature rise characteristics of the metal powders were obtained within a microwave field. Further, the composition change law of the composites was determined during the sintering process by analyzing the properties and microstructure of the composites. The successful development of this strategy will provide a reliable reference for the application of microwave sintering in the fabrication of MBDC.

The hot-press technique is applied to lower the sintering temperature and shorten the sintering process of Li1.5Al0.5Ge1.5(PO4)3 (LAGP). The hot-press conditions are studied to obtain well sintered LAGP pellet with high Li ion conductivity. The highest Li ion conductivity is obtained at 550 oC for 30 min at 7 MPa and the values are 3.8, 3.4 and 1.8×10-4 S cm-1 in bulk, grain-boundary and total conductivities, respectively. These values are comparable to reported values, however, sintering temperature is more than 250 oC lower and holding time is more than several hours shorter than conventional sintering processes.

The overlaid laminated bamboo lumber (OLBL) was developed for structural applications with an aim to substitute commonly-used building materials such as steel and concrete. The OLBL was, via a hot press, fabricated by cross-laminating bamboo layers, bamboo mats and phenolic impregnated adhesive papers. Since the weight of OLBL was governed by the high density bamboo layer, the panels made of OLBL had a relatively high density value of about 850 kg/m3. In this study, a lightweight panel was developed by a proper arrangement of radial bamboo curtain. The major and minor directions of a panel were the parallel- and perpendicular-to-its length direction, respectively. It was found that 1) the density of an OLBL panel could be reduced by about 20%; 2) the failure occurred in the bamboo node(s); 3) there was a significant difference in effective modulus of elasticity and effective modulus of rupture between two panel directions; and 4) there was a good relationship between the density and strength in the minor direction.

The use of press hardening steel (PHS) in structural safety-related parts has experienced a rapid growth in the automotive industry, due to increased passenger safety standards, which require an improved vehicle intrusion resistance. Very small concentrations of diffusible hydrogen in ultra-high strength PHS deteriorate their mechanical properties. The focus of the present study was the analysis of the diffusible hydrogen uptake during the hot press forming process of the aluminized PHS and its impact on the mechanical properties of PHS. The effect of the paint baking on the properties of aluminized PHS was also evaluated by mechanical testing and hydrogen thermal desorption analysis. A mechanism for the hydrogen absorption of aluminized PHS was proposed.

To further improve the vibration damping behavior of carbon fiber composite sandwich structures without too much redundant weight, empty and foam filled corrugated sandwich cylindrical panels (CSCPs) are designed and their corresponding modal characteristics are investigated experimentally and numerically. Axial and circular CSCPs (ACSCPs and CCSCPs) are simultaneously manufactured by a hot press moulding and post-assembly approach. It has been demonstrated that foam filled CSCPs can obviously improve the structural damping compared to the empty CSCPs without significant change of the corresponding natural frequencies. Furthermore, validated finite element analysis (FEA) models are adopted to systematically study the effects of the corrugated inclination angle, sandwich core thickness, arc-length and topological corrugated configurations on the modal properties. Several conclusions are drawn, which may be useful for the multifunctional design of such kinds of composite sandwich structures.

In this study, poly (glycidyl methacrylate-co-styrene) (PGS) emulsions were synthesized through a free radical initiated emulsion polymerization of glycidyl methacrylate (GMA) and styrene. The PGS was characterized with FTIR, and investigated as a curing agent for soybean flour (SF)-based wood adhesives. Seven-ply plywood panels were prepared with the SF-PGS adhesives and were evaluated for their water resistance through a three-cycle water-soaking test. Effects of the PGS/SF weight ratios, hot press temperature, hot press time, and usage of NaOH on the water resistance of the resulting plywood panels were investigated. Decrease in the relative amount of GMA in the PGS reduced the effectiveness of the PGS as a curing agent in the SF-PGS adhesives. Plywood panels made with the SF-PGS adhesives met the industrial requirement for interior plywood.

In this study the effect of veneer densification on the temperature change inside the plywood during the hot pressing step was analyzed. In addition, the shear strength of the plywood was determined. Rotary-cut birch veneer and phenol-formaldehyde resin were used to make the plywood samples. The multi-layers plywood structures made of densified and non-densified veneers with and without adhesive were investigated. Plywood products of 3, 5, 7, 9 and 11-layers were manufactured under laboratory conditions. It was found that the multi-layers plywood made of densified veneers was heated faster when compared to the plywood made of non-densified veneers. This will reduce the pressing time of plywood made of densified veneer by 2–29% depending on the number of veneer layers. The shear strength values of the plywood made of densified veneers were found two times higher than the normalized value of 1.0 MPa, meeting the EN 314-1 standard requirements. Findings of this work are useful for industrial applications to optimize the plywood production.

W and Al2O3 heterogeneous materials was bonded by using Cr as transition layer, and the diffusion behavior and resulted mechanical strength was studied. Results show that, Cr can diffuse and form metallurgical bonding with both W and Al2O3, and thus connect the heterogeneous materials together. The higher the sintering temperature and time is, the larger the diffusion distance and bonding strength is. Diffusion of Cr in W is defined as diffusion limited, while that in Al2O3 can be considered as interface controlled. Rate constants are 1.79 × 10−7 m/s−1/2 and 3.59 × 10−9 m/s, and kinetic exponent n can be considered as 0.5 and 1, respectively.

The purpose of this study is to establish a press forming process for carbon fiber reinforced thermoplastics (CFRTP). This paper discusses the formation phenomena including deformation behavior of plain weave CFRTP and the press load behavior during formation. In addition, the influence of press load conditions and the cooling rate of CFRTP sheets under pressure on the mechanical strength of the formed products are discussed, as well as the influence of slide speed on the temperature of the CFRTP sheet during their formation.

Self-assembly of monodisperse colloidal microspheres is a significant approach to construct structural color materials. However, background light interference and point contact among the microspheres result in poor color visibility and mechanical strength. In this work, self-supporting structural color films with excellent stability and flexibility were fabricated using monodispersed polysulfide (PSF) colloidal microspheres with intrinsic light-absorpting characteristic, simultaneously incorporating the polyacrylate (PA) flexible network through interfacial adhesion. More interestingly, multicolor pattern output on standard cotton can be achieved through continuous hot press. Owing to its satisfactory stability and flexibility, the fabric has high resistance to washing and friction, thus ensuring the normal effect in harsh conditions. This study provides a promising solution for the construction of flexible structural color materials to be applied in packaging, decoration, and colorful coating.

Hot press forming (HPF) steel sheets are austenitized, press-formed, and rapidly cooled to obtain a martensitic microstructure with an ultra-high strength. When they are insufficiently austenitized, their microstructures might contain a small amount of untransformed ferrite, which can deteriorate impact toughness as well as strength, but its causes and relevant fracture mechanisms have not been clearly verified yet. In this study, thus, 1.8-GPa-grade HPF sheets were austenitized at various temperature and time, and their tensile and Charpy impact test results were analyzed in relation with untransformed ferrite and its effect on fracture mechanisms. In the HPF sheets containing the untransformed ferrite, voids were formed mostly at ferrite/martensite interfaces, and were grown and propagated linearly to form a cleavage crack, whereas deformation bands were well developed without voids or cracks in the non-ferrite-containing sheets. The highly localized strains accommodated in the soft ferrite made ferrite/martensite interfaces or ferrite itself work as fracture initiation sites, which led to the brittle fracture and consequently to the deterioration of impact energy. This result can provide an important idea for optimization of austenitization conditions demanded for ultra-high strength and excellent impact toughness in HPF applications.

In present research work, a method has been established through powder metallurgical route to produce β-FeSi 2 thermoelectric material without giving long time mechanical alloying treatment to the elemental powders and long duration heat treatment cycle. The elemental powders of iron (98.9% purity, 200 mesh) and silicon (98.5% purity, 400 mesh) have been mechanically alloyed for 6 h using high-energy Attritor ball-mill and was subjected to Hot Press Sintering (HPS). Effect of HPS parameters on density of compacts was studied. The compacts with higher densities (82–92% relative density) were later on subjected to the thermal cycling treatment. The density as well as the amount of β-FeSi 2 phase formation got enhanced due to thermal cycling treatment.

Joining of TiAl to Ti alloy is a potential requirement for manufacturing the components with dual properties. In this paper, the hot-press bonding of Ti-33Al-3V to TC17 was implemented at different pressures and the temperature of 850 °C for 10 min with post bond heat treatment. The influence of pressure on interfacial microstructure evolution and atomic diffusion was analyzed in detail. The microstructure observation and phase composition analysis on the bond indicate that the metallurgical bonding of Ti-33Al-3V/TC17 is produced at pressures of 23–50 MPa, and an interfacial zone with a certain width forms between base alloys. A new α 2 (Ti 3 Al) phase is generated in the interfacial zone. The influence of pressure on the metallurgical bonding of Ti-33Al-3V/TC17 includes two aspects. One is to promote the void shrinkage in the interfacial zone. The quantitative analysis of voids shows an increase in pressure induces a decrease in amount and size of voids. The highest bonding ratio of 96.3% can be obtained at the pressure of 50 MPa with post bond heat treatment. The second is to promote the atomic diffusion across bond line. The diffusion distances of Ti and Al atoms increase with an increase in pressure and the width of the interfacial zone shows a linear increasing law with the pressure. Moreover, a higher pressure induces a higher increment in atomic diffusion distance and width of the interfacial zone in the post bond heat treatment.

This study attempted to develop an additive-free dried sweet potato snack. To provide a crispy texture, sweet potatoes were dried by a two-stage process. At the first drying stage, steamed sweet potatoes were semi-dried for 6 h using hot-air convection or pulsed infra-red (IR) radiation, and drying rate was compared under varying sample thicknesses and drying temperatures. The IR exhibited enhanced drying speed, particularly the IR radiation at 60 °C was favorable for application to the drying of sweet potatoes with large thickness. For the secondary drying, the IR-dried sweet potatoes with varying moisture content were applied to hot-press (HP) drying at 180 °C for 2 s. The quality of final products indicated that the crispy texture of the products was generated when the semi-dried sample had a moisture content lower than 0.5 kg/kg dry base (d.b.). When the moisture content of samples prior to HP process was lower than 0.3 kg/kg d.b., the final product was easily broken with discoloration to dark-brown. Considering the entire processing procedure, the present study demonstrated that IR radiation at 60 °C for 5 h followed by HP was an effective combination for the mass production of a crispy sweet potato snack.

This study introduces enhanced corrosion performance of the Al-Si-Mg coated 22MnB5 boron steel. Structural changes of the coating after hot-dip-aluminizing and hot-press-forming processes with the presence of Mg included compacter surface with Mg segregation and thicker crack-free layer. Electrochemical corrosion tests indicated higher polarization resistance from the Al-Si-Mg sample compared to the reference Al-Si sample, especially in an early period of immersion. Such enhanced anti-corrosion performance can be attributed to the aforementioned structural changes and pore-filling effect of corrosion products. This study depicts that the Al-Si-Mg coating can be considered as another option for hot-press-forming steel by its enhanced barrier protection vs. Al-Si coating.

This work reports the development of a composite material from both renewable resources and biodegradable materials: modification of poly-lactic acid (PLA) with rice straw fibre loading. PLA-RS fibres composites were prepared with different fibre loadings (5 – 15 vol%) with different layout sequence; sequential layering and batch-mixed using hot press. The flexural strength of the PLA-RS fibre composites prepared using the both sequential layering and batch-mixed reduced with increasing fibre loading but for batch-mixed, the flexural strength increased at 10 vol% fibre loading and reduced again thereafter. In this case, RS fibres were not able act as reinforcement for PLA.

This paper describes work carried out to fabricate and to assess the fibre orientation in PLA reinforced by aligned discontinuous harakeke and hemp fibre mats produced using a dynamic sheet former (DSF). These mats were combined with PLA sheets to make composites with fibre contents of 5–40 wt% using a hot press. It was found that the fibre orientation factors ( K θ ) for both harakeke and hemp fibre composites were higher than those values seen in the literature for composites prepared using injection moulding and hot pressed using randomly oriented fibre mats, but slightly lower than the highest values obtained with aligned fibre nonwoven preform composites utilising more processing stages. The highest K θ values for harakeke and hemp fibres in this work were found to be 0.58 and 0.44 respectively. K θ decreased, reflecting increased fibre misalignment as fibre content increased, believed to be due to fibre agglomeration and the higher pressure required during processing.

A tribological performance was carried out on different types of hot press Sialon ceramics regarding the phases, i.e., the α-Sialon phase, the β-Sialon phase, and the α/β-Sialon composite phase. The different phases of Sialon ceramics were analyzed by XRD patterns. For the tribological performance, the Sialon ceramics were laser textured and the starved lubrication method was applied with different dimple pitches under a load of 10 N at room temperature. The material having a dimple pitch of 200 µm shows the lowest coefficient of friction. The α/β-Sialon composite phase shows the least coefficient of friction i.e. 0.04 and 0.1 for the textured and polished (without being textured) samples, respectively. The Sialon ceramics show mild wear and therefore, the wear rate of the steel ball (mating partner) was taken into account for the wear analysis. The α-Sialon phase having a higher hardness shows the least wear in comparison to the α/β-Sialon composite phase and the β-Sialon phase.

Cu/AlMgB 14 composites with different AlMgB 14 amounts were fabricated by hot press sintering. The influences of the sintering temperature and the AlMgB 14 content on the tribological and mechanical properties of the composites were preliminarily investigated. In short, a lower sintering temperature leads to a lower friction coefficient but relatively poor mechanical properties, while the opposite results are shown at higher sintering temperature. Besides, raising the AlMgB 14 concentration to some extent can markedly reduce the friction coefficient and the wear rate of the composites. Especially when sintered at lower temperature, the composites with 10 wt% AlMgB 14 or above have the lowest friction coefficient of 0.2.

Alumina toughened zirconia (ATZ) ceramic composites are prepared by both oscillatory pressure sintering (OPS) and hot press (HP) at various temperatures and times. The density and grain size of the resultant samples are measured and compared to illustrate the effect of oscillatory pressure on the sintering behavior of the material. The results reveal that there is a critical temperature, above which OPS can retard grain growth compared to HP. The grain growth rate in OPS-sintered sample is several times lower than those in HP-sintered sample. The phenomenon was discussed in terms of plastic deformation. These results clearly show that OPS is a better method for sintering the composite compared to HP.

The mechanical performance of continuous large tow carbon fiber reinforced polyamide 6 laminates fabricated by hot press molding was studied using quasi-static and dynamic tests. The effects of layup, strain rate and high temperature were discussed. The results show that the thermoplastic composites possess strain rate strengthening effects and high temperature weakening dependence. Different layup laminates exhibit different sensitivities. The elastic modulus difference of unidirection/cross-ply laminates decreases but that of unidirection/quasi-isotropic or unidirection/angle-ply laminates increases with the increasing strain rate. However, the failure strength difference changes insignificantly as the strain rate increases. The modulus or strength difference between unidirectional laminate and the other laminates decreases with the increasing temperature. The weakening effect of high temperature is stronger than the strengthening effect of strain rate for tensile mechanical properties. Furthermore, the failure behavior and mechanism were analyzed. These experimental data and research results could provide some insight for high-performance thermoplastic composites.

In this research, Co–30Cr–6Mo alloys were fabricated by vacuum hot-press sintering technique. The experiments utilized various hot-press sintering temperatures (1100 °C, 1150 °C, 1200 °C and 1250 °C) and hot-press pressures (20, 35 and 50 MPa) to find the optimal parameters for Co–30Cr–6Mo alloys, while simultaneously investigating the differences in microstructural characteristics and properties. The experimental results showed that the optimal hot-press sintering parameters of this sample were 1150 °C at 35 MPa for 1 h. Meanwhile, Co–30Cr–6Mo alloys possessed the optimal mechanical and electrical properties. Among them, the sintering density reached 8.13 ± 0.01 g cm−3, the hardness and TRS increased to 78.9 ± 0.2 HRA and 2672.2 ± 25.8 MPa, respectively, and the electrical conductivity was 3.11 ± 0.95 × 104 S m−1. TEM observation also identified the stacking faults, FCC and HCP structures of the Co phase, and the partial Cr23C6 carbides precipitated in the Co–30Cr–6Mo alloys, respectively. Consequently, the sintering characteristic of Co–30Cr–6Mo was effectively improved, and the mechanical properties were enhanced at a relatively lower sintering temperature by the vacuum hot-press sintering process.

Functional gradient hydroxyapatite reinforced polyetheretherketone is one of the most promising orthopedic implant biomaterials. In this study, functional gradient hydroxyapatite reinforced polyetheretherketone biocomposites were prepared by layer-by-layer method with the incorporation of hot press molding technology. Studies on the flexural mechanical properties of the functional gradient biocomposites revealed that the flexural stress–stain behavior of the biocomposites presented linear elastic characteristics. The fracture mechanism of the functional gradient biocomposites was predominated by brittle rupture. Furthermore, both flexural strength and break strain of the functional gradient HA/PEEK biocomposites obviously decreased with the rise of the total HA content. The effect of hydroxyapatite concentration difference between adjacent layers (HCDBAL) on the flexural strength obviously relied on the level of HCDBAL and total HA content in the functional gradient HA/PEEK biocomposites. The higher the total HA content in the functional gradient biocomposites is, the less the influence degree of HCDBAL on the flexural strength is. Moreover, total HA content and HCDBAL played synergistic influence on the flexural modulus of the functional gradient HA/PEEK biocomposites.

The 70 wt.% (TiC x N y –TiB 2 )/Ni composites were fabricated successfully by the combustion synthesis and hot press consolidation of the Ni–Ti–Al–B 4 C–BN powder mixtures. The addition of Al to Ni–Ti–B 4 C–BN system significantly decreased the ignition difficulty of combustion synthesis, and improved the compression properties of (TiC x N y –TiB 2 )/Ni composites. The final products mainly consist of Ni, TiC x N y and TiB 2 , and the ceramic particles distribute uniformly in the composites. With increasing Al content from 0 to 8 wt.%, the average sizes of the TiC x N y and TiB 2 particles decrease a little, while the hardness and the compression strength increase firstly and then decrease, and the fracture strain increases. The composite with optimal 5 wt.% Al possesses the best comprehensive properties: the highest hardness (1794 Hv), the superior compression strength (3.76 GPa), and the fracture strain (4.2%), resulting in an overall increase by ~ 15%, ~ 28%, and ~ 45%, compared with these of the composite without the Al addition, respectively.

Gd-doped monazite-(Ce) ceramics (Ce 0.9 Gd 0.1 PO 4 ) have been fabricated by hot-press sintering (HPS) and pressureless sintering (PLS). The influence of sintering temperature and holding time on the bulk density and microstructure was investigated. The results show all of HPS samples are denser than the PLS samples, even if the optimal PLS temperature is as high as 1400 °C and the HPS temperature is only 1150 °C. Low-temperature densification of the HPS ceramics should be attributed to particle rearrangement under pressure. In addition, chemical durability testing was carried out using the standard MCC-1 static leach test method. The results indicate that the normalized elemental leach rates of HPS samples are higher than those of PLS sintered specimens before 21 days, and remained almost unchanged ( R L (Ce)≤6.0×10 −6 g m −2 d −1 , R L (Gd)≤1.8×10 −5 g m −2 d −1 ) in both HPS and PLS ceramics after 28 days. The low-temperature HPS process to prepare monazite-based ceramic is a promising method for immobilizing trivalent minor actinide.

Triphenyl phosphate (TPP) is widely used as a flame retardant (FR). However, recent studies have indicated that FRs like TPP can be detected in household dust and wildlife and could contribute to obesity and osteoporosis in humans. We hypothesize that the formation of an inclusion complex (IC) between TPP and β-cyclodextrin (β-CD) will reduce its toxicological effects, while retaining the flame retarding properties of TPP, since the formation of FR-CD-ICs is expected to eliminate unnecessary loss of FRs, especially volatile FR compounds like TPP, and release them only during a fire when they are actually needed. After creating the TPP-β-CD-IC, we applied it to polyethylene terephthalate (PET) films by a hot press technique. Untreated PET films, as well as PET films embedded with uncomplexed β-CD and TPP, were prepared in the same way and had comparable thicknesses. Flame tests were conducted for all film samples by following a modified ASTM D 6413 standard. TPP-β-CD-IC exhibited flame resistant performance matching that of neat TPP, even though much less TPP was contained in its β-CD-IC. Incorporation of FRs and other chemical additives into textile substrates in the form of their crystalline CD-ICs is a promising way to reduce the exposure of hazardous chemicals to humans and to our environment while not impacting their efficacy.

The 50 vol.% (TiCx–TiB2)/Cu composites were successfully fabricated by the method of combustion synthesis and hot press consolidation in a Cu–Ti–B4C–Zr system. The effect of the content of Zr on the microstructures, hardness, compression properties and abrasive wear behaviors of the composites was investigated. The final products consist of only Cu, TiCx and TiB2, and the ceramic particles distribute uniformly in the composites. The sizes of the ceramic particles decrease with Zr addition. With the increasing Zr content, the yield strength, ultimate compression strength and hardness increase, and the fracture strain decreases. The abrasive wear resistance of the composites increases with the increase in the Zr content.

Composite thick films of xPoly(vinylidene-fluoride)-(1−x)[0.8(Bi0.5Na0.5)TiO3-0.2CoFe2O4] with x = 0.1, 0.2, 0.3 and 0.4 were synthesized by hot press method. X-ray diffraction pattern of the composite films indicate the existence of distinct peaks of poly(vinylidene-fluoride), (Bi0.5Na0.5)TiO3 and CoFe2O4 phases. The value of dielectric loss and saturation magnetization of polymer composite films decrease with increase in poly(vinylidene-fluoride) content. The magnetodielectric effect of the polymer composite films was found to improve with increasing poly(vinylidene-fluoride) content. The linear fitting of Δe ∼ γM2 gives the value of magnetoelectric interaction coefficient (γ) of polymer composite films.

Unidirectional flax fiber reinforced composites (FFRC) were made by hot press. Effects of processing parameters, including curing pressure, time and temperature on the distribution, shape and content of the voids formed during the manufacturing process of FFRC were investigated. The voids were characterized with the aid of ultrasonic C-scan and optical microscopy. Tensile and interlaminar shear properties of FFRC containing different content and shape of the voids were tested. The results showed that the voids were easily trapped in both the intralaminar and inside the flax yarns of FFRC due to the distinct structural characteristics of flax fibers. The relationships between voids and mechanical properties of the composites were established.

The hot press bonding of γ-TiAl alloy and TC17 alloy was successfully conducted at a low bonding temperature of 850 °C by imposing plastic deformation of TC17 alloy and post heating at 840 °C for 60 min. The results indicate that the effect of plastic deformation and heating on the microstructure and microhardness of diffusion zone is very significant while this effect on base alloys can be ignored. The increasing plastic deformation of TC17 alloy and heating promote the shrinking of voids and the increasing of the width of diffusion zone because of the enhancing atom diffusion. A sound metallurgical bond with the microhardness in a narrow range of 314–345 HV is obtained by imposing a percentage of TC17 deformation of 50% and post heating.

High-temperature self-lubricating nickel-alloy based composites with Ag and three amounts of BaF 2 /CaF 2 eutectic were prepared by hot press sintering technique. Both the composites with 5 wt% and 10 wt% BaF 2 /CaF 2 eutectic exhibited markedly higher strength than 15 wt% composite. The friction coefficient of the three composites was comparable. All three composites showed the highest wear rate at 600 °C, but very lower at 800 and 900 °C. The friction coefficient of the three composites was slightly lower as sliding against Si 3 N 4 than Inconel 718. The friction and wear mechanism was proposed.

Boron suboxide (B 6 O) based materials containing TiB 2 additions were produced in this study via two routes (non-reactive and reactive sintering) and were consolidated using a hot press, which was operated between the temperatures of 1800–1900 °C and at an applied pressure of 50 MPa for 20 min dwelling time. Relationships between the formed phases, microstructures and mechanical properties of the sintered materials were established. The density was higher in the reactive sintered materials with finer microstructure than in the non-reactive sintered counterpart. Generally, the mechanical properties of the B 6 O–TiB 2 materials were enhanced when compared to the pure B 6 O material.

Compression tests of the TiAl and TiAl–2Mn alloys have been performed in the strain rate range from 1 × 10−5 s−1 to 1 × 10−2 s−1, and the effect of strain rate on the compression properties and work-hardening behavior of the two alloys have been investigated. Under any strain rate, the ultimate compression strength ( σ true UCS ) and the fracture strain ( e true f ) of the TiAl–2Mn alloy are better than those of the TiAl alloy, while the work-hardening capacity (Hc) of the TiAl–2Mn alloy is lower than that of the TiAl alloy. The yield strength ( σ true y ) and Hc of the two alloys are strain rate sensitive, while the σ true UCS and e true f are insensitive to the strain rate. With the increase in the strain rate, the σ true y increases, while the Hc decreases.

Waste rubber (WR) powder was introduced in a two-roll mill in the presence of various ratios of curatives to develop sheets of devulcanized waste rubber (DWR). The selected product was investigated by FTIR, TGA and SEM. In a roll mill and hot press, styrene butadiene rubber (SBR) gum was differentially replaced by DWR feed ratios, and thereafter irradiated with gamma rays. The mechanical parameters of the developed blend were examined. Oil resistance and thermogravemetric behavior were discussed. Remarked improvement in the mechanical, thermal and physical parameters of SBR was generally determined by the incorporation of DWR and gamma irradiation.

The dry-sliding tribological behaviors of Ti–46Al–2Cr–2Nb intermetallics and its composites with 20 and 40 vol% in situ formed TiB2 produced by hot press sintering process were investigated. Also, the microstructures and mechanical properties of the three materials were examined. With the increase of TiB2 amount, the hardness and wear resistance ascended. The enhanced wear resistance can be attributed to the higher hardness and the load-carrying role of TiB2. The friction coefficient was irrespective of TiB2 content. The wear mechanism of the materials was dominated by fatigue wear and delamination.

The (TiB 2 –TiC x N y )/(Ni + W) composites were fabricated successfully by the method of combustion synthesis and hot press consolidation in the Ni–W–Ti–B 4 C–BN system. The effect of the content of W on the hardness, compression properties and abrasive wear behavior of the composites was investigated. The results indicate that with increasing W content from 0 to 8 wt.%, the average sizes of the TiB 2 and TiC x N y particles decrease firstly and then keep almost constant, while the hardness and the compression strength increase firstly and then change a little. The abrasive wear resistance of the composites increases firstly and then decreases with the increase in the W content.

The TiAl matrix composites reinforced with nano-TiB2 and nano-Ti5Si3 particles were successfully fabricated by the in situ method of combustion synthesis and hot press consolidation. The sizes of the synthesized TiB2 and Ti5Si3 particles are about 30–50 nm and 60–80 nm, respectively. The synthesized nano-TiB2 particles could significantly enhance the ultimate compression strength ( σ true UCS ) of the TiAl alloy, and the σ true UCS increases with the increase in the TiB2 content. The average σ true UCS of the 6 vol% TiB2/TiAl composite is 477 MPa higher than that of the TiAl alloy. The synthesized nano-Ti5Si3 particles could improve the strength and ductility of the TiAl alloy simultaneously, and the σ true UCS and fracture strain ( e t r u e f ) increase first and then decrease with the increase in the Ti5Si3 content. The average σ true UCS of the 4 vol% Ti5Si3/TiAl composite is 171 MPa higher than that of the TiAl alloy, and the average e t r u e f increases from 17.3% to 20.9%.

Imprinting technique is an efficient method for fabricating microstructures for microfluidics and lab-on-chip applications. However such technique is not commonly used for glass based microstructures fabrication. In this study, microstructures were transferred completely and successfully from a nickel alloy stamp to different glasses such as sodalime glass, Pyrex glass, SGBN glass and magneto optical glasses, using imprinting technique. Furthermore, the traditional vacuum hot press for imprinting was replaced with the conventional electric furnace which increases the cost efficiency and simplicity greatly. Using specific mold in the conventional furnace, the mass production of microstructured glass chips can be realized.

The diamond cutting tools (DCTs) find vast applications in the stone cutting industries. The properties of marbles/stones vary from mine to mine. The main factor judging the performance of the tool is its wear resistance which is primarily affected by materials/process variables and unpredictable working conditions. The DCTs having composition (by wt.%) of 13.5% Cu, 20% Co, 10% FTC, 6% Al, and 1% Mg and balance thermally reduced electrolytic iron powder were blended in a mixer with ball to powder ratio of 10:1 (by wt.%) for 2 h. Then this blended powder is mixed manually with synthetic diamonds (2.88%) and 2% paraffin wax. The blended powder was green compacted to size 20 mm × 10 mm × 4.5 mm in hot-pressed sintering furnace. The sintering response of DCT was studied and it was correlated with its wear performance in dry sliding Pin-On-Disc wear test machine having sintered alumina as the counterface. These specimens were subjected to varying loads (2, 6, 10, and 12 kg) and varying velocities (1, 2, 3, and 4 m/s) for wear test. The 2D contour was drawn to establish transition in wear modes from adhesive wear to abrasive wear.

The 40–60 vol.% TiC x –TiB 2 /Cu composites were successfully fabricated by the combustion synthesis and hot press consolidation in a Cu–Ti–B 4 C system. The final products consist of only Cu, TiC x and TiB 2 , and the ceramic particles distribute uniformly in the composites. The sizes of the ceramic particles decrease with the increasing Cu content. The yield strength, ultimate compression strength and microhardness increase with the increasing TiC x –TiB 2 content. The incorporation of the TiC x –TiB 2 particles improves the wear resistance of the composites effectively, and the wear resistance increase with the increase in the TiC x –TiB 2 content.

The (TiB 2 –TiC x N y )/Ni composites were fabricated by the method of combustion synthesis and hot press consolidation in a Ni–Ti–B 4 C–BN system. The effect of Ni content on the microstructure, hardness, compression properties and abrasive wear behavior of the composites has been investigated. The results indicate that with the increase in Ni content from 30 wt.% to 60 wt.%, the average size of the ceramic particles TiB 2 and TiC x N y decreases from 5 μm to ≤ 1 μm, while the hardness and the abrasive wear resistance of the composites decrease. The composite with the Ni content of 30 wt.% Ni possesses the highest hardness (1560.8 Hv) and the best abrasive wear resistance. On another hand, with the increase in the Ni content, the compression strength increases firstly, and then decreases. The composite with 50 wt.% Ni possesses the highest compression strength (3.3 GPa). The hardness and fracture strain of the composite with 50 wt.% Ni are 1251.2 Hv and 3.9%, respectively.

The purpose of this study was to investigate the physico-mechanical properties and characteristics on reduction of formaldehyde from UF particleboards as furniture materials under urea treatment. Straw particle were treated at three levels of urea concentration (5%, 10%, 15%) and 95 °C as holding temperature. Particleboards were manufactured using hot press at the temperature of 180 °C and the pressure of 3 MPa with two types of UF adhesive (UF-45, UF-91). Then the formaldehyde emission values and physical, mechanical properties were considered. The results indicated that the specimens under urea treatment had better mechanical and physical properties in comparison with control specimens. Also specimens manufactured under urea treatment at 10% concentration and UF-91 type adhesive had the most physical and mechanical strength. Furthermore, the results showed that by increasing urea concentration, the formaldehyde emission value was decreased.

The Ti 2 AlC/TiAl composites are successfully fabricated utilizing the method of the combustion synthesis and hot press consolidation in the Ti–Al–Nb–C system and the effect of the (Nb–C) content on the compression properties and work-hardening behavior of the composites has been investigated. The compression properties and work-hardening capacity of the TiAl alloy improve remarkably with the addition of the (Nb–C) elements due to the formation of Ti 2 AlC particles and the solid solution of Nb in the TiAl matrix. The compression properties of the composites increase first then decrease with the increase in the (Nb–C) content and the TiAl–10 wt.% (Nb–C) sample possesses the best comprehensive compression properties and the highest work-hardening capacity.

Powders of Al 4 C 3 and SiC were combined by high-energy milling to produce Al 4 SiC 4 , Al 4 SiC 4 + 30 vol.% TiC, and Al 4 SiC 4 + 30 vol.% WC. Five different temperatures were used to hot press the constituents. XRD, SEM, relative density, and hardness measurements showed that formation of single-phase Al 4 SiC 4 occurred at 1450 °C and full densification (99%) was achieved at 1500 °C. Both of these temperatures are lower than previously reported. Adding TiC and WC increases hardness, while WC improves densification (99.5%).

This work studied fungal bioresistance of combined hydro-thermo-mechanically modified (CHTM) poplar wood. The CHTM technique, introduced by Mohebby et al. (2009) , is a combination of two wood modification techniques–hydrothermal wood modification and densification of wood. Blocks of poplar wood were initially treated hydrothermally at temperatures of 120, 150, and 180 °C for holding times of 0, 30, and 90 min. Afterwards, the treated blocks were compressed by a hot press (160 and 180 °C) for 20 min with a compression set of 60%. After the CHTM-treated blocks were dried, small specimens were cut for soft-rot and brown-rot decay tests according to ENV 807 and EN 113. Mass losses as well as metabolic moisture contents were determined in the decayed samples. Results revealed that the combination of wood modification techniques showed fungal suppression. It was also found that the hydrothermal treatment step could significantly reduce fungal attack in comparison with densification. Reduction of the mass losses was associated with the hydrothermal treatment temperature. Also, the level of metabolic moisture content was correlated with the mass losses for both fungi. Any reduction of the mass loss decreased the moisture content in the wood.

In the present study, nearly dense polycrystalline magnesium fluoride ceramics were fabricated by hot-press sintering, using bimodal size distribution MgF2 powder. Densification was carried out at 710 °C under 300 MPa pressure for 60 min. The effect of weight percent of ultrafine powder on densification and also transparency, hardness and density of the samples produced are discussed. The results shown that sample with 15 wt.% ultrafine component, has the highest transparency, density, hardness, and a well developed microstructure, containing the lowest amount of porosities with small size.

In this study the W/Cu and W/ZrC composites have been fabricated by hot-press and then their mechanical properties were compared in addition to their ablation resistance. To produce W-20vol.%Cu composite at first stage the elemental W and Cu powders were ball milled for 3 h in rotation speed of 200 rpm, in which 2% nickel was added in order to reduce the density. The mixed powders were hot-pressed for 1 h at 1400 °C and compact pressure of 30 MPa. Additionally W/40vol.%ZrC composite has been fabricated by hot-pressing of mixed W and ZrC powders in 30 MPa and 2200 °C for 1 h. Since these materials are used at elevated temperature applications, where ablation is the main source of material failure, after producing the composites their ablation resistance was evaluated in a real condition. The results show that not only W–ZrC composite is better than W–Cu composite in mechanical properties, but also in ablation resistance.