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In this paper, ITO films prepared by RF magnetron sputtering, and ITO and FTO films purchased were used as research objects. Ultraviolet-visible spectrophotometer was used to characterize the film transmittance of the samples. The results show that both ITO and FTO films exhibit good optical transmittance. Scanning electron microscope (SEM) was used to observe the surface morphology of the films, and the surface of all the films was relatively uniform. X-ray photoelectron spectroscopy (XPS) was used to characterize the elemental, composition, valence and electronic state information of the sample surface. The results show that the preparation method and annealing treatment affect the elemental composition and valence of the sample surface, and this information has a certain correlation with the electrical and optical properties of the film. The above research results provide reference for the design and performance improvement of new transparent conductive films. [ABSTRACT FROM AUTHOR]

During the crystallization process of certain racemic compounds, spontaneous resolution can lead to distinctive external appearances of enantiomeric crystal forms. This article offers a comprehensive overview and delineates four methods for identification, namely, examining hemihedral faces, assessing macromorphology, employing circular polarization, and analyzing surface topography. These identification techniques serve as invaluable tools and viewpoints for studying the crystallization behavior of chiral compounds, holding significant potential across diverse applications in pharmaceutical production, materials science, and chemical synthesis. [ABSTRACT FROM AUTHOR]

BACKGROUND: Synthetic calcium phosphate ceramic materials are similar to the inorganic components of natural bone tissue. Functional design through surface morphology and chemical composition can endow them with excellent osteoconductive and osteoinductive properties. The development of calcium phosphate ceramic materials with osteoinductive properties is the current research hotspot. OBJECTIVE: To endow the submicron topology tricalcium phosphate ceramics with osteoinductive properties through material morphology regulation and functional design, and test their physicochemical properties and osteoinductive properties. METHODS: Novel tricalcium phosphate ceramics were prepared by high temperature sintering method. Clinical available Bio-oss bone meal was set as the control group. The sample surface morphology, the protein adsorption capacity, and the in vitro mineralizability of the two materials were characterized. Human periodontal membrane stem cells at passage 3 were co-cultured with the extracts of the two materials. Cell proliferation was detected by CCK-8 assay. Alizarin red staining was used to detect cell mineralization performance. The human periodontal ligament stem cells at passage 3 were seeded on the surfaces of the two materials. Early osteogenesis was detected by alkaline phosphatase staining. The expression of osteogenesis-related factors was detected by qRT-PCR. RESULTS AND CONCLUSION: (1) Scanning electron microscope exhibited that both materials had microporous surfaces with granular texture. Bio-Oss particles were significantly smaller than that of tricalcium phosphate ceramics. The total porosity, macroporosity, and microporosity were similar for both materials. Tricalcium phosphate ceramics were mainly submicron pores, with a grain size of 100 nm-1.0 μm. Bio-Oss bone meal was mainly nano-scale pores. In vitro mineralization experiments displayed that the ability of the surface of tricalcium phosphate ceramics to induce bone apatite deposition was stronger than that of Bio-Oss bone meal. Compared with Bio-Oss bone meal, tricalcium phosphate ceramics could adsorb more proteins from fetal bovine serum and bovine serum albumin solution (P < 0.05). (2) CCK-8 assay demonstrated that both materials promoted cell proliferation, and there was no significant difference between the two groups (P > 0.05). (3) The alkaline phosphatase activity in the tricalcium phosphate ceramic group was higher than that in the Bio-Oss group at 4 and 7 days of culture (P < 0.05), and the number of mineralized nodules at 21 days of culture was more than that in the Bio-Oss group; the mRNA expression levels of alkaline phosphatase, osteocalcin, osteopontin and Runx-2 were higher than those in the Bio-Oss group on 7 and 14 days of culture (P < 0.05). (4) The results showed that the new calcium phosphate ceramics have superior in vitro osteoinductive properties. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To review various methods and research progress of the application of trunk surface morphometry in vertebral column defects in recent years, and summarize the limitations and development trend of trunk surface morphometry. METHODS: The first author searched the literature published from 1980 to 2021 on PubMed, Web of Science, CNKI, and Wanfang databases. The key words were “vertebral column defects, spinal deformation, scoliosis, trunk surface, surface topography, TS, AIS, screening”. After excluding repetitive and poor-quality studies, a total of 72 articles were included for analysis. RESULTS AND CONCLUSION: (1) As a non-radiation detection method, the safety of trunk surface morphometry is higher than that of radiological examination, but its accuracy is still controversial because this method is an indirect way to infer the degree of spinal curvature. At present, it cannot replace the special status of radiological examination in the diagnosis and treatment of abnormal spinal curvature diseases. (2) At present, the measurement of trunk surface morphology is divided into three categories: one is the physical examination based on Adam’s test and trunk rotation angle measurement. It has been used in the screening of scoliosis for a long time. To improve the accuracy of the examination, a variety of examinations need to be used together, and the detection efficiency is low. The second is the two-dimensional image measurement method represented by the Trunk Aesthetic Clinical Evaluation and posterior trunk symmetry index, which is often used for the regular monitoring of patients with abnormal spinal curvature. The third is three-dimensional imaging detection represented by Moire image, structured light and Formetric system. In recent years, after breaking through the technical bottleneck, it has got rid of its inefficient and harsh measurement conditions. The measurement accuracy is higher than two-dimensional image measurement. It is widely used in the clinical work of spinal deformity. (3) In recent years, more efficient spinal deformity screening methods developed by relying on new information technologies such as artificial intelligence and big data have also been reported from time to time. When improving the existing trunk surface morphology measurement, optimizing the existing trunk surface morphology measurement or creating a new measurement index can further improve the accuracy and effectiveness of the trunk surface morphology measurement and expand its scope of use under the conditions of meeting the requirements of direct measurement, using clear and accurate anatomical landmarks, simplifying the measurement scheme and clarifying the normal threshold of the index. [ABSTRACT FROM AUTHOR]

Spindle rotation error affects the machining accuracy of turning workpieces. Through analyses and studies of the spindle rotation error， a 2-D surface topography detection method was proposed for turning workpieces based on the rotation error， and the turning process model was established. The MATLAB simulation results showed that the spindle radial rotation error affects the turning radius and surface topography of the workpiece， resulting in the coaxiality error， roundness error and surface roughness. To verify the effectiveness of the proposed method， the 2-D surface topography detection platform for data collection was built， and the rotation error value of the spindle in the depth direction and average radius error of turning workpieces were obtained. The experimental results showed that the experiment and simulation results are consistent in characteristics， which verify the feasibility of the method and have reference value for the performance debugging of the machine tool and improving the processing quality of the workpieces. [ABSTRACT FROM AUTHOR]

In order to explore the evolution mechanism of surface corrosion of pre-stress grinding and the influence of grinding parameters on the corrosion resistance of stainless steel, 304 stainless steel was taken as the research object, a numerical model considering the influence of pre-stress grinding surface topography on the corrosion resistance of stainless steel was established. Firstly, the phase field equation for the corrosion field of rough surfaces was derived. Secondly, the surface topography model of the workpiece of pre-stress grinding was established. Finally, an auto-correlation wheel surface model with non-Gaussian distribution characteristics was built. With all the built models, the corrosion resistance of pre-stressed grinding surfaces was explored. Compared with the existing research results, the conclusions obtained conform to the general law, which verifies the rationality of the proposed method. The results showed that the pre-stress grinding surface has the "polishing effect" in the corrosive environment. As the corrosion time extends, the surface corrosion resistance is enhanced. In the condition of using coolant, appropriately increasing the pre-stress, wheel speed, and reducing feed speed can improve the corrosion resistance of the machined surface. When the pre-stress is a fixed value, the method of optimizing the linear speed and feed speed of the grinding wheel could also be used to further improve the corrosion resistance of the stainless steel workpiece. [ABSTRACT FROM AUTHOR]

In order to obtain the relationship between the roughness parameters and the uniformity of the surface wear and the surface roughness of the friction pair, the current-carrying experiments were carried out under different experimental conditions. And the effect of contact current, contact pressure, sliding speed and running time on the roughness parameters was analyzed. When the other experimental conditions keep constant, the longer the running time and the greater the sliding speed, the greater the roughness of the contact surface, and the wear is more uneven. The greater the contact pressure, the smaller the roughness, and the wear is more uneven. The greater the contact current and the greater the contact, the surface roughness value decreases first and then increases slightly, and the wear becomes more and more uniform. [ABSTRACT FROM AUTHOR]

BACKGROUND: Biomedical implants have been widely used in various orthopedic treatments. However, the existing bone implants often have the disadvantages of poor mechanical properties, immune response, microbial infection, poor healing and so on. Different surface modification techniques can effectively make up for these shortcomings. OBJECTIVE: To summarize the surface modification techniques of the current bone tissue engineering implants. METHODS: The first author searched the PubMed, CNKI, and VIP datadase to retrieve the article regarding repair of tuberculous bone defect published during 2000-2009 with the search terms "'bone tissue engineering; bone implant; surface modification; coating" in Chinese and English, respectively. The articles published recently or in high-impact journals were included in this study. RESULTS AND CONCLUSION: The surface of bone tissue engineering implants was modified by inorganic and organic components or by changing the surface topography of the implants. This improves the osteogenesis, bone conductivity, bacteriostasis，and biocompatibilily of bone implant to different degrees. However, we, need to solve some problems before this new implant is applied to the clinic: how to determine the optimal concentration of different surface modification componets, maximize bone healing, inhibit bacterial activity, and avoid other adverse reactions; how to avoid foreign body reaction and immune response caused by particles generatedby surface abrasion of these bone tissue engineering implants over time; how to incorporate various growth factors, proteins and other biological molecules into the coating without damaging their respective chemical structures and functions; how to guide the release of growth factors and molecules in a coordinated and controllable way. [ABSTRACT FROM AUTHOR]

BACKGROUND: Previous studies have shown that titanium nanotubes with different diameters effect the adhesion and growth of cells on the implant surface. OBJECTIVE: To investigate the effects of annealing treatment on the biological behaviors of fibroblasts on the surface of TiO2 nanotubes with different diameters. METHODS: TiO2 nanotubes were prepared by polishing pure titanium samples through anodizing at 5 V and 20 V respectively, and then annealed. The pure titanium samples were divided into six groups: P (polishing titanium), NT5 (TiO2, nanotubes prepared at 5 V), NT20 (TIO2 nanotubes prepared at 20 V), A-P (annealing treatment and polishing titanium), A-NT5 (TiO2, nanotubes prepared at 5V and annealed) and A-NT20(TiO2, nanotubes formed at 20 V and annealed). Field emission scanning electron microscopy was used to obsesrve the surface topography. Fibroblasts were inoculated on the surface of each group of samples. After 60 and 120 minutes of culture, the number of cells adhering to titanium sample surface was counted using cell nucleus staining method. On day 1 of culture, cell morphology was observed using scanning electron microscopy. On days 1, 3 and 5 of culture, cell proliferation was detected by MIT method. On day 3 of culture, the secreation of collagen fiber was detected by picro-sirius red staining method. RESULTS AND CONCLUSION: (1) The annealing treatment had no significant effect on the morphology and diameter of the nanotubes. (2) The number of adherent cells in the NT5 and NT20 groups was significantly lower than that in the P group. The annealing treatment the number of fibroblasts on the surface of polished pure titanium and decreased the number of fibroblosts in the NT5 and NT20 groups. (3) Annealing enhanced the viability of fibroblasts on the surface of polished pure titanium and decreased the viability of cells on the surface of nanotubes prepared at 5 and 20 V. (4) Cell viability in the NT5 and NT20 groups was lower than that in the P group. Annealing treatment increased the viability of cells on the surface of polished pure titanium and decreased the viability of cells on the surface of nanotubes prepared at 5 and 20 V. (5) The level of collagen on the surface of nanotubes in the NT5 and NT20 groups was higher than that in the P group. Annealing treatment increased the level of collagen on the surface of polished pure titanium and decreased the level of collagen in the NT5 and NT20 groups. These findings suggest that TiO2, nanotubes inhibit the adhesion, spreading and proliferation of fibroblasts to different degrees; annealing treatment can enhance this inhibitory effect; TiO2, nanotubes enhance collagen secreation by fibroblasts to different degrees, and annealing treatment inhibits the enhancement. [ABSTRACT FROM AUTHOR]

Using chromium nitrate, chromium (VI) oxide, calcium dichromate trihydrate or potassium dichromate as precursors, chromium catalysts for propane dehydrogenation are prepared. The nominal chromium loading in the catalyst is 11 Wt%. The propane dehydrogenation activity of the catalyst is investigated under the conditions of Weight hourly space velocity CWHSV) of Cl. 7 h 1 and reaction temperature of 600 °C. XRD, SEM, NH3TPD, H3-TPR and CV-vis are used to charact erize the crystal structure, surface topography, surface acidity, surface reducibility, and chromium valence of different precursors catalysts. The propane dehydrogenation activity of the catalyst is measured with a fixed-bed miniature reaction device. The high-frequency infrared carbon-sulfur analyzer, thermal cracking GC- III S, and in-situ DRIFTS are used to analyze the amount of coke deposited, the type of coke deposited, and the reaction intermediates. The results shmv that the catalyst Cr ( III )-RC with chromium nitrate or Cr (VD-RC with chromium (VJ) oxide as precursor have mainly weak acid sites on the surface, and its high-valent chromium (Cr6+) is easily reduced, the propane conversion and propylene selectivity are higher. The catalyst Cr(VI)-Ca-RC with wlcium dichromate trihydn1te or Cr( Vl) -K-RC with potassium di chromate as precursor have mainly medium-strength acid sites on the surface, and its high-valent chromium (Cr6+) is not easily reduced, the side reactions are strong, and the propane conversion and propylene selectivity are lower. Adjusting the surface acidity of the catalyst reasonably and promoting the reduction of high-valent chromium (Cr6+) will be beneficial to the preparation of high-performance chromium-based propane dehydrogenation catalysts. [ABSTRACT FROM AUTHOR]

Ｔｏ ｓｔｕｄｙ ｔｈｅ ｇｒｉｎｄｉｎｇ ｐｒｏｃｅｓｓ ｐｅｒｆｏｒｍａｎｃｅ ｏｆ ２.５Ｄ Ｃｆ / ＳｉＣ ｃｏｍｐｏｓｉｔｅｓꎬ ｓｉｎｇｌｅ ｆａｃｔｏｒ ｔｅｓｔｓ ｗｅｒｅ ｄｅｓｉｇｎｅｄ ａｎｄ ｅｘｅｃｕｔｅｄ. Ｔｈｅ ｒｅｓｕｌｔｓ ｓｈｏｗ ｔｈａｔ ｇｒｉｎｄｉｎｇ ｄｅｐｔｈꎬ ｗｈｅｅｌ ｓｐｅｅｄ ａｎｄ ｆｅｅｄ ｓｐｅｅｄ ｈａｖｅ ｐｒｏｍｉｎｅｎｔ ｉｎｆｌｕｅｎｃｅ ｏｎ ｔｈｅ ｐｒｏｃｅｓｓｉｎｇ ｐｅｒｆｏｒｍａｎｃｅ ｅｖａｌｕａｔｉｏｎ ｐａｒａｍｅｔｅｒｓꎬ ｉｎｃｌｕｄｉｎｇ ｓｕｒｆａｃｅ ｔｏｐｏｇｒａｐｈｙꎬ ｓｕｒｆａｃｅ ｒｏｕｇｈｎｅｓｓ ａｎｄ ｇｒｉｎｄｉｎｇ ｆｏｒｃｅ. Ｉｔ ａｌｓｏ ｉｍｐｌｉｅｓ ｔｈａｔ ｔｈｅ ｇｒｉｎｄｉｎｇ ｄｅｐｔｈ ｉｓ ｔｈｅ ｍａｘｉｍａｌ ｉｎｆｌｕｅｎｃｅ ｆａｃｔｏｒꎬ ｗｈｉｌｅ ｆｅｅｄ ｓｐｅｅｄ ｉｓ ｔｈｅ ｍｉｎｉｍａｌ ｏｎｅ. Ｄｕｅ ｔｏ ｄｉｆｆｅｒｅｎｃｅ ｏｆ ｓｕｐｐｏｒｔｉｎｇ ｅｆｆｅｃｔｓ ｏｆ ｔｈｅ ｗａｒｐ ｆｉｂｅｒ ａｎｄ ｗｅｆｔ ｆｉｂｅｒꎬ ｔｈｅ ｄｅｆｅｃｔ ｆｏｒｍｓ ｏｎ ｔｈｅ ｍａｃｈｉｎｅｄ ｓｕｒｆａｃｅ ａｒｅ ｄｉｆｆｅｒｅｎｔ. Ｔｈｅ ｍａｉｎｌｙ ｓｕｒｆａｃｅ ｄｅｆｅｃｔｓ ｏｆ ２.５Ｄ Ｃｆ / ＳｉＣ ｃｏｎｔａｉｎ ｉｎｔｅｒｆａｃｉａｌ ｄｅｂｏｎｄｉｎｇꎬ ｃｒａｃｋꎬ ｆｉｂｅｒ ｏｕｔｃｒｏｐ ａｎｄ ｐｕｌｌｏｕｔ. Ｉｎ ａｄｄｉｔｉｏｎꎬ ｄｉｆｆｅｒｅｎｔ ｇｒｉｎｄｉｎｇ ｃｈｉｐｓ ｗｏｕｌｄ ｂｅ ｐｒｏｄｕｃｅｄ ｗｉｔｈ ｄｉｆｆｅｒｅｎｔ ｇｒｉｎｄｉｎｇ ｐａｒａｍｅｔｅｒｓ ａｎｄ ｆｉｂｅｒ ｏｒｉｅｎｔａｔｉｏｎｓ. Ａｃｃｏｒｄｉｎｇ ｔｏ ｔｈｅ ｅｘｐｅｒｉｍｅｎｔａｌ ｒｅｓｕｌｔｓꎬ ｔｈｅ ｇｒｉｎｄｉｎｇ ｍｅｃｈａｎｉｓｍ ｏｆ ２.５Ｄ Ｃｆ / ＳｉＣ ｗａｓ ｒｅｓｅａｒｃｈｅｄ ｉｎ ｄｅｔａｉｌꎬ ｗｈｉｃｈ ｓｕｐｐｌｉｅｓ ｓｉｇｎｉｆｉｃａｎｔｌｙ ｔｅｃｈｎｉｃａｌ ｓｕｐｐｏｒｔ ｆｏｒ ｉｎｖｅｓｔｉｇａｔｉｏｎ ｏｎ ｔｈｅ ｇｒｉｎｄｉｎｇ ｔｈｅｏｒｙ ｏｆ ２.５Ｄ Ｃｆ / ＳｉＣ. [ABSTRACT FROM AUTHOR]

Objective · To propose a method for making organ-on-a-chip based on 3D printing, and study the relationship between cell growth on the chips and various factors. Methods · Through 3D printing technology and surface microstructure transfer method, ulcer-like and ridge-like microstructures of the tumor surface and the intestinal villi were fabricated on a polydimethylsiloxane (PDMS) chip. Combined with fluorescence imaging, the effects of surface modification, shapes and heights of microstructures, and culture time on the surface coverage and density of Caco-2 cells on the chip were measured. Results · The PDMS chip was more likely to induce cell adhesion and growth rather than the 3D printing resin chip. On the surface of three-dimensional structure, cell surface coverage and cell density increased after the surface was treated with rat tail collagen Ⅰ (PP0.000). After surface modification, there was no significant difference in cell density at the same height of different steric structure (P>0.05). Conclusion · The intestinal villi and tumor topological organ chips can be fabricated3D printing technology and surface microstructure transfer method. The surface modification and microstructure height affect the cell growth on the surface. [ABSTRACT FROM AUTHOR]

Objective · To propose a method for making organ-on-a-chip based on 3D printing, and study the relationship between cell growth on the chips and various factors. Methods · Through 3D printing technology and surface microstructure transfer method, ulcer-like and ridge-like microstructures of the tumor surface and the intestinal villi were fabricated on a polydimethylsiloxane (PDMS) chip. Combined with fluorescence imaging, the effects of surface modification, shapes and heights of microstructures, and culture time on the surface coverage and density of Caco-2 cells on the chip were measured. Results · The PDMS chip was more likely to induce cell adhesion and growth rather than the 3D printing resin chip. On the surface of three-dimensional structure, cell surface coverage and cell density increased after the surface was treated with rat tail collagen Ⅰ (PP0.000). After surface modification, there was no significant difference in cell density at the same height of different steric structure (P>0.05). Conclusion · The intestinal villi and tumor topological organ chips can be fabricated3D printing technology and surface microstructure transfer method. The surface modification and microstructure height affect the cell growth on the surface. [ABSTRACT FROM AUTHOR]

The specific rate of breakage(S○1)and primary breakage distribution(Bi,j)of untreated and microwave-treated vanadium titano-magnetite(VTM) with different particle size were investigated using grinding kinetics， and the variations of surface topography and phase composition of ground products were analyzed. The results show that the breakages of both untreated and microwave-treated VTM obey the first-order grinding kinetics. The S○1 of microwave-treated VTM is higher than that of untreated ore and the S1 increment increases with increasing particle size. The primary breakage distribution parameters(γ) are dependent upon the feed particle size. The γ value of Bi,j of microwave-treated VTM is less than that of untreated ore. The SEM analysis shows that the ground products have smaller particle size and rougher surface after microwave treatment. The XRD analysis shows that microwave-treated VTM has stronger diffraction peaks and larger amounts of gangue phases after ball mill， compared to those of untreated ore， which indicates that the degree of dissociation of ore is improved. [ABSTRACT FROM AUTHOR]

The lunar surface topography mapping is the basic work of the lunar exploration and plays an important role in the three-phase (“around-fall-back”) lunar exploration program. In the “around” phase, it is necessary to use the camera carried by the spacecraft to acquire high-resolution image of area around the drop-off point. Due to the low orbit altitude and the limited field of view of camera, the width of the imagery obtained by the lunar satellite is relatively small compared to the range of the required drop-off area. Multiple strips stitching is an effective and practical way to solve large regional imaging problem. In a given multiple strips stitching task planning, it is required to optimize the sideswing angle of each orbit within a given mission duration to meet the regional coverage demand. To meet the requirements of region multiple strip stitched imaging task,an lateral swing optimization of method is proposed in this paper. Firstly, a fast algorithm based on vector polygon logical operation is proposed. Coverage polygons of each imaging strip are calculated based on the lateral swing angle, satellite orbit and the field of view of the sensor, then the coverage ratio can he computed via a Boolean operation between target polygon and strip coverage polygons. The proposed method of coverage ratio calculation can not only ensure the accuracy of calculation, hut also can dramatically reduce its computation complexity. Secondly, a lateral swing angle optimization model for multiple strip stitching imaging task is introduced, which uses swing angle as decision valuables, coverage ration maxi-mization as objective function respectively , and an improved adaptive genetic algorithm based on sigmoid function is proposed to solve the optimization model. Finally, two simulation experiments are executed to validate the validity of proposed method. [ABSTRACT FROM AUTHOR]

At present， most studies about the seal are based on the assumption that the seal surface topography and friction conditions are changeless. The influence of the seal surface topography on the leakage is mostly ignored as well as the effect of the microscopic perspective. Based on the fractal theory， the contact between surfaces of dynamic and static rings was simplified to the contact between rough surface and the ideal rigid plane， and a mechanical seal leakage model was established. The effects of fractal parameters， the surface unit load and material parameters on leakage rate were studied to obtain that the mechanical seal fractal dimension D and the end face specific load p○g were inversely proportional to the leakage amount Q. The characteristic length scale parameter G and the comprehensive elastic modulus E were proportional to its leakage amount Q. The calculated leakage rate and experimental data verify the accuracy of the model. [ABSTRACT FROM AUTHOR]

The work aims to study tribology performance of dialkyl dithiocarbamic borate ester. A new extreme pressure and anti-wear additive of dialkyl dithiocarbamic borate ester(CNSB) was synthesized. When dialkyl dithiocarbamic borate ester was added to the base oil in proper proportions, the result was lubricating oil. Tribology performance of various lubricating oil was investigated by using a four-ball tester. Surface topography of wear scar was observed through scanning electron microscopy. By observing wear scar diameter, friction coefficient, maximum nonseizure load and surface topography of wear scar, the tribology performance and friction mechanism was investigated. With the increase of quality fraction of additive CNSB, friction coefficient, wear scar diameter and friction coefficient decreased rapidly, but the maximum nonseizure load increased significantly. The wear scar diameter of oil samples with 1.5% addition amount of CNSB decreased by 28.95%. The friction coefficient of oil samples with 2.0% addition amount of CNSB decreased by 34.48%. The maximum nonseizure load of oil samples with 2.0% addition amount of CNSB increased by 539 N. In the course of friction, the synthetic CNSB was decomposed. The appeared active S elements and a small number of N and B elements formed lubrication protective film, resulting in lower friction coefficient and good wear resistance. [ABSTRACT FROM AUTHOR]

In the NaCl-KCl-NaF-NiO molten salt system, nickel plate was used as the anode and copper plate as the cathode. The dense Cu-Ni functionally graded material (FGM) was prepared by electrodeposition. The composition of molten salt, current waveform and current density were studied. The influence of electrodeposition conditions such as molten salt temperature, electrodeposition time on the surface morphology and thickness of the deposited layer was analyzed to determine the best process conditions. The surface composition and fracture morphology of Cu-Ni FGM were also analyzed. The results show that different molten salt compositions have great influence on the surface quality of the electrodeposited layer. The best process conditions for the electrode- posited Cu-Ni gradient material are; current waveform is pulsed current; electrodeposition temperature is 700 °C ; current density is 70 mA/cm²; electrodeposition time is 30 min. [ABSTRACT FROM AUTHOR]

Ｔｈｅ ｅｆｆｅｃｔｓ ｏｆ ｓｕｒｆａｃｅ ｔｏｐｏｇｒａｐｈｙ ｏｎ ｔｈｅ ｆｒｉｃｔｉｏｎ ｎｏｉｓｅ ｗｅｒｅ ｓｔｕｄｉｅｄ ｕｎｄｅｒ ｔｈｅ ｅｌａｓｔｏ⁃ ｈｙｄｒｏｄｙｎａｍｉｃ ｌｕｂｒｉｃａｔｉｏｎ （ＥＨＬ） ｃｏｎｄｉｔｉｏｎ． ２ ｋｉｎｄｓ ｏｆ ｇｒｏｏｖｅ⁃ｔｅｘｔｕｒｅｄ ｓｕｒｆａｃｅ ｔｏｐｏｇｒａｐｈｉｅｓ ｗｅｒｅ ｆａｂｒｉｃａｔｅｄ ｂｙ ｌａｓｅｒ ｔｅｘｔｕｒｉｎｇ ｏｎ ｔｈｅ ｓｕｒｆａｃｅ ｏｆ ｔｈｅ ｍｅｔａｌ ｄｉｓｃ ｓｐｅｃｉｍｅｎ． Ｆｒｉｃｔｉｏｎ ｎｏｉｓｅｓ ａｎｄ ｆｒｉｃｔｉｏｎ ｃｈａｒａｃｔｅｒｉｓｔｉｃｓ ｏｆ ｄｉｆｆｅｒｅｎｔ ｓｕｒｆａｃｅ ｔｏｐｏｇｒａｐｈｉｅｓ ｗｅｒｅ ｔｅｓｔｅｄ ｏｎ ａ ｍｏｄｉｆｉｅｄ ＪＰＭ⁃１ ２⁃ｄｉｓｃ ｔｒｉｂｏ⁃ｔｅｓｔｅｒ． Ｔｈｅ ｅｆｆｅｃｔｓ ｏｆ ｄｉｆｆｅｒｅｎｔ ｏｐｅｒａｔｉｎｇ ｃｏｎｄｉｔｉｏｎｓ ａｎｄ ｓｕｒｆａｃｅ ｔｏｐｏｇｒａｐｈｉｅｓ ｏｎ ｔｈｅ ｆｒｉｃ⁃ ｔｉｏｎ ｎｏｉｓｅ ｕｎｄｅｒ ｌｉｎｅ ｃｏｎｔａｃｔ ＥＨＬ ｃｏｎｄｉｔｉｏｎｓ ｗｅｒｅ ａｎａｌｙｚｅｄ， ａｎｄ ｔｈｅ ｒｅｓｕｌｔｓ ｗｅｒｅ ｖｅｒｉｆｉｅｄ ｗｉｔｈ ｔｈｅ ｆｉｎｉｔｅ ｅｌｅｍｅｎｔ ａｎａｌｙｓｉｓ． Ｔｈｅ ｗｏｒｋ ｓｈｏｗｓ ｔｈａｔ， ｖａｒｉａｔｉｏｎｓ ｏｆ ｔｈｅ ｌｏａｄ ａｎｄ ｔｈｅ ｒｏｔａｔｉｏｎａｌ ｓｐｅｅｄ ｈａｖｅ ｓｉｇｎｉｆｉｃａｎｔ ｅｆｆｅｃｔｓ ｏｎ ｔｈｅ ｌｉｎｅ ｃｏｎｔａｃｔ ｆｒｉｃｔｉｏｎ ｎｏｉｓｅ． Ｓｉｎｃｅ ｔｈｅ ｌｉｎｅ ｃｏｎｔａｃｔ ｐａｉｒｓ ｕｓｕａｌｌｙ ｗｏｒｋ ｉｎ ａ ｐａｒｔｉａｌ ＥＨＬ ｃｏｎｄｉｔｉｏｎ， ｔｈｅ ｆｒｉｃｔｉｏｎ ｎｏｉｓｅ ｃｈａｒａｃｔｅｒｉｓｔｉｃｓ ａｒｅ ｓｉｍｉｌａｒ ｔｏ ｔｈｏｓｅ ｏｆ ｄｒｙ ｆｒｉｃｔｉｏｎ： ｔｈｅ ｓｕｒｆａｃｅ ｗｉｔｈ ａ ｌａｒｇｅｒ ｆｒｉｃｔｉｏｎ ｃｏｅｆｆｉｃｉｅｎｔ ｗｉｌｌ ｒａｄｉａｔｅ ｓｔｒｏｎｇｅｒ ｆｒｉｃｔｉｏｎ ｎｏｉｓｅ． Ｓｐｅｃｉｆｉｃ ｔｏｐｏｇｒａｐｈｉｅｓ ｃａｎ ｉｍｐｒｏｖｅ ｔｈｅ ｌｕｂｒｉｃａｔｉｏｎ ｃｈａｒａｃｔｅｒｉｓｔｉｃｓ ｏｆ ｔｈｅ ｓｕｒｆａｃｅ， ａｎｄ ｅｆｆｅｃｔｉｖｅｌｙ ｒｅｄｕｃｅ ｔｈｅ ｓｏｕｎｄ ｐｒｅｓｓｕｒｅ ｌｅｖｅｌ ｏｆ ｔｈｅ ｆｒｉｃｔｉｏｎ ｎｏｉｓｅ． Ｔｈｅ ｐｒｅｓｅｎｃｅ ｏｆ ｇｒｏｏｖｅ ｔｅｘｔｕｒｅｓ ｃａｎ ｉｎｔｅｒｒｕｐｔ ｔｈｅ ｓｔｒｅｓｓ ｄｉｓｔｒｉｂｕｔｉｏｎ ｏｆ ｔｈｅ ｃｏｎｔａｃｔ ａｒｅａ ａｎｄ ｗｅａｋｅｎ ｔｈｅ ｉｍｐａｃｔ ｂｙ ｓｕｒｆａｃｅ ａｓｐｅｒｉｔｉｅｓ， ｔｈｅｒｅｂｙ ｒｅ⁃ ｄｕｃｉｎｇ ｔｈｅ ｓｅｌｆ⁃ｅｘｃｉｔｅｄ ｖｉｂｒａｔｉｏｎ． Ａｔ ｔｈｅ ｓａｍｅ ｔｉｍｅ， ｔｈｅ ｐｒｏｐｅｒ ｓｕｒｆａｃｅ ｔｏｐｏｇｒａｐｈｙ ｓｔｒｕｃｔｕｒｅ ｉｓ ａｌｓｏ ｈｅｌｐｆｕｌ ｉｎ ｔｈｅ ｆｏｒｍａｔｉｏｎ ｏｆ ｌｕｂｒｉｃａｔｉｎｇ ｏｉｌ ｆｉｌｍ， ｈｅｎｃｅ ｌｏｗｅｒｉｎｇ ｔｈｅ ｆｒｉｃｔｉｏｎ ｎｏｉｓｅ ａｓ ｗｅｌｌ ａｓ ｔｈｅ ｆｒｉｃｔｉｏｎ ｅｎｅｒｇｙ ｏｆ ｔｈｅ ｓｙｓｔｅｍ． [ABSTRACT FROM AUTHOR]

Aiming at the problem of the surface roughness of substrate on the coating which is impacted, spreaded and solidified. three-dimensional model of droplet jetting substrate was built, and the processing model of the layered deposition was established. Based on this, the influence of different surface roughness of substrate on the surface morphology of coating was analyzed.the simulation data was imported into the software MATLAB,three-dimensional surface topography of the layered surface after deposition and solidifcation was simulated under the condition of different surface roughness.Based on the analysis of simulation data,the quality of the coating surface topography is described according to profile arithmetic average error Ra , ten-point height of irregularities Rt and maxium altitude Ry value of contour under the condition of different surface roughness of substrate.The simulation results show that with the increasing of the suface roughness,the spreading areas of layer gradually become large,the thickness is more uniform and the surface morphology becomes better within an appropriate range. [ABSTRACT FROM AUTHOR]

For the machinability difficulty of GH4169 Ni-based superalloy and 5A06 Al-Mg alloy as well as the high demands of machined surface quality and machining precision, the ultrasonic vibration assisted turning machining system was designed utilizing the method of ultrasonic vibration, which proceeded with cutting principle and machining technology. The contrast test was conducted to compare ultrasonic vibration assisted turning with conventional turning for these two alloy materials. The results indicate that the technological parameters have obvious effect on the surface roughness, surface topography and chip morphology of machined workpiece when ultrasonic vibration assisted turning of Ni-based superalloy and Al-Mg alloy is conducted. Choosing reasonable technological parameters can promote efficiently the processing quality, and enable the machining effects of ultrasonic vibration assisted turning to be superior to that of conventional turning. [ABSTRACT FROM AUTHOR]

The milling experiments of C/SiC composite with PCD tools are conducted, and surface formation mechanism is analyzed by observing surface/subsurface damages. The effect of milling parameters on surface topography and surface roughness is discussed with the analysis of cutting force. The results show that C/SiC composite is removed in the mechanism of brittle fracture. Laminated fracture, pull-out and fracture in bundle of carbon fiber can be observed on the machined surface. The effect of milling parameters on surface roughness is basically the same with that on surface topography. The higher cutting speed can improve the surface quality, the bigger axial depth of cut will worsen the surface quality and the feed per tooth has no significant influence on surface quality. [ABSTRACT FROM AUTHOR]

High-strength carbon fiber reinforced polymer (CFRP) with unidirectional laminate structure has gradually developed into major materials in load-bearing aerospace components, and relevant demand in cutting and machining is increasing. Owing to significant anisotropy, CFRP materials with unidirectional laminate structure incline to produce defects and are typical difficult-to-machine materials. By orthogonal cutting experiments, cutting force, specific energy, cutting temperature and machined surface are obtained when cutting T700 high-strength CFRP unidirectional laminates under different fiber orientations. Based on experimental results, mechanical and thermal anisotropy of CFRP uniform laminates are discussed, specific energy maps under different cutting parameters are achieved, heat sources are studied, and the conduction model is established. By scanning electron microscope (SEM) topography of typical surfaces, surface formation mechanism under different fiber orientations is given. [ABSTRACT FROM AUTHOR]

High-strength carbon fiber reinforced polymer (CFRP) with unidirectional laminate structure has gradually developed into major material in load-bearing components in aerospace, and the cutting demand of CFRP is increasing. Because of the significant anisotropy, CFRP laminates highly tend to produce defects and are typical difficult-to-machine materials. Orthogonal cutting experiments on T800 high-strength CFRP unidirectional laminates are conducted to study the variation of cutting force, torque and cutting temperature with different fiber orientations. Based on the drilling experiments with brad point drill and multifacet drill, the effects of cutting force, torque and cutting temperature on defect forming process are discussed, and SEM topography of hole wall surface with typical defects is given. Through analyzing the wall surface of drilling holes, defect formation mechanism under different drilling processes is given. [ABSTRACT FROM AUTHOR]

The surface quality of polymer-bonded-explosive( PBX) is a key factor to influence the explosive components and the weapons. An avalanche phenomenon, which is created by material, process and operating condition, on the cutting surface of PBX is observed by analyzing the cutting surface 3D-contour of PBX, which causes the difference between 2D arithmetical mean deviation of the profile and 3D arithmetical mean deviation of the profile to be 32%. Hence, a prediction model which consideres the multiple factors is established with the RBF neural network. The training and test of the prediction model illustrates that the model could reflect the regularity of cutting process, and the predicted error is within 2% . [ABSTRACT FROM AUTHOR]

Electrical discharge dressing (EDD) process is a non-traditional promising truing and dressing technology for superabrasive wheels. The process makes use of electrical energy to melt and vaporize the wheel bond, and make the abrasive grains stick from the grinding wheel. The development of lightning leader displays a stochastic discharge channel with branching and tortuous structure during EDD. It obviously has characteristic of self-similarity, which can be well described by fractals. A discharge channels simulation model based on the fraetal theory shows the thermal energy distribution of various discharge mediums on the diamond wheel. And various discharge mediums including kerosene-based oil, impressed air and misted deionized water, are applied on EDD bronze-bonded diamond grinding wheels. The surface topography of dressed diamond grinding wheel is observed by VHX-1000 three-dimensional digital microscope. The analyses indicate that the surface topography of dressed diamond grinding wheel is consistent with the feature of simulation discharge channel based on the fraetal theory. At the same time, the fractal simulation model of discharge channels is benefit to predict the wheel dressing microstructure and fressing quality. [ABSTRACT FROM AUTHOR]