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Using TC4 titanium alloy powder as raw material, selective laser melting ( SLM) forming experiments and numerical simulation were conducted to investigate the influence of process parameters on the properties of the forming parts with equal laser energy density. The results show that the laser power and scanning speed have significant effects on the molten pool size at the constant laser energy density. The powder layer thickness is the most important factor affecting the surface roughness of the sample, and the optimal powder layer thickness is 0. 03 mm. Although the laser energy density is the same, the surface morphology and microstructure of the sample are still affected by the combination of different process parameters. No significant effect is found on the surface hardness of SLM deposition under different process parameter combinations at equal laser energy density. [ABSTRACT FROM AUTHOR]

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To prepare structured fish scale surfaces on brittle and difficult-to-process materials, the topological features of fish scale surfaces are first extracted, and a surface model of fish scale units is established. This fish scale model is then used to construct the structured fish scale surface. Next, based on the principle of micro-abrasive air jet processing, the feasibility of air jet processing for topological fish scale experiments and the important process parameters affecting the morphology of the structured fish scale surface are analyzed. Finally, using the single-factor experimental method, the important processing parameters are experimentally analyzed to obtain a better topological fish scale surface unit, and the structured surface is arranged accordingly. The research results show that a reasonable combination of process parameters for micro-abrasive jet machining of structured topological fish scale surfaces includes a machining time of 10s, a machining pressure of 0.5 MPa, a stand-off distance of 10 mm, and a jet angle of 30°. Despite the potential for certain effects on the morphology and size of the fish scale surface, the topological properties of the fish scale surface remain unchanged using the proposed machining method.

Copyright of Diamond & Abrasives Engineering is the property of Zhengzhou Research Institute for Abrasives & Grinding 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 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]

Copyright of Lubrication Engineering (0254-0150) is the property of Editorial Office of LUBRICATION ENGINEERING 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 China Mechanical Engineering is the property of Editorial Board of China Mechanical Engineering 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 Journal of Mechanical Strength / Jixie Qiangdu is the property of Zhengzhou Research Institute of Mechanical Engineering 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 China Mechanical Engineering is the property of Editorial Board of China Mechanical Engineering 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 Machine Tool & Hydraulics is the property of Guangzhou Mechanical Engineering Research Institute (GMERI) 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.)

Low-profile electrolytic copper foils were prepared by direct-current electrodeposition with only gelatin as an additive. The effects of some process conditions such as surface roughness of titanium substrate (i.e. cathode), current density, mass concentrations of sulfuric acid and copper ions, and electrolyte temperature on the surface morphology and roughness of the electrodeposited copper foil were studied. The optimal process conditions were determined as follows: surface roughness (Rz) of titanium substrate 1-2 μm, current density 4.0 A/dm², sulfuric acid 100 g/L, copper ions 60 g/L, and electrolyte temperature 37 ². The copper foil electrodeposited under the optimized conditions exhibited good surface morphology with a roughness (Rz) of lower than 1.8 μm. [ABSTRACT FROM AUTHOR]

To study the influence of grain arrangement on the surface profile of the workpiece, a mathematical model and its corresponding analytical algorithm of pyramidal abrasive belt grinding were established. The roughness value was simulated and predicted with Abaqus software. Grinding tests were carried out on the robot grinding system platform with pyramidal abrasive belt, and the surface profile were inspected and then compared with the simulation. The results show that the simulated roughness and the measured values have similar variation trend with good consistency, where the error is within 0.03 μm and the maximum error rate is 16.6%. The theoretical simulation and test results remain consistent, indicating that the model could be used to predict the surface roughness of workpiece ground with pyramidal abrasive belt.

Copyright of China Mechanical Engineering is the property of Editorial Board of China Mechanical Engineering 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 Electroplating & Finishing is the property of Electroplating & Finishing 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.)

Addressing the issue of unequal distribution of residual compressive stress and high surface roughness that occurs on gears after shot peening treatment, this research examined the impact of double shot peening technology on the surface integrity of 18CrNiMo7-6 carburized gear steel. Using the Abaqus software,a random pellet distribution shot peening model was created. The effects of shot peening parameters such as shot peening speed and shot diameter on the surface residual stress and surface topography of 18CrNiMo7-6 carburized gear steel were analyzed. The findings indicate that double shot peening yields more uniform surface plastic deformation in comparison to single shot peening. Additionally, the second shot peening can significantly increase the residual compressive stress on the surface of the material, and shifts the depth of maximum residual compressive stress value towards the surface. However, this process does not significantly affect the depth of the residual compressive stress layer. Through variance analysis, when the shot peening coverage is 100%, the second shot peening strengthening is carried out by using the processing parameters with smaller shot peening intensity,which has a better improvement effect on the uniformity of surface layer residual compressive stress, and the uniformity of surface residual compressive stress is increased by 28.76%.

Copyright of China Mechanical Engineering is the property of Editorial Board of China Mechanical Engineering 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.)

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]

In order to investigate the wear characteristics of pantograph slide in pantogragh-catenary under different current, contact pressure and sliding speed, current-carrying wear experiments were carried out to study the current-carrying efficiency, arc energy, friction coefficient and temperature of the friction pair under different working conditions. The wear area of the slide was measured in blocks and multiple times after the experiments, and the surface topography images and roughness parameters of the slides were collected by metallographic microscope and surface roughness instrument respectively. An image processing method based on Otsu algorithm was used to extract pits from the topography images and perform mark calculation, and the variation of the area and number of pits, and the roughness parameters (contour arithmetic mean deviation and maximum contour valley depth) under different working conditions was statistically analyzed. The results show that with the increase of current, the area and number of pits increase, and the roughness parameters decrease. With the increase of contact pressure, the area of pits decreases, the number of pits decreases first and then increases slightly, and the roughness parameters decrease. With the increase of sliding speed, the area and number of pits and the roughness parameters increase. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Donghua University (Natural Science Edition) is the property of Journal of Donghua University (Natural Science) 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 Lubrication Engineering (0254-0150) is the property of Editorial Office of LUBRICATION ENGINEERING 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.)

Rolling finishing cut is a new kind of micro machining technology. It can remove the traces on the material surface， reduce the roughness of the tooth surface and reduce the meshing noise of the gear. An experimental study on finishing cut of aviation spiral bevel gears is carried out using parallel spindle rolling finishing technology. The machining mechanism of this finishing technology is described， and the relative movement between finishing abrasive and gear surface is studied. According to the cutting formula of abrasive at the outer circle of gears， the influence law of various factors is analyzed. The experimental results show that: the surface finishing of spiral bevel gears can be significantly improved by this kind of rolling finishing technology； the roughness Ra value of cone shaft tooth surface decreases from 0.8 to 0.4； the roughness Ra value of cone disk decreases from 0.8 to 0.3； the consistency of tooth surface texture is obviously improved. These lay a foundation for further research on vibration and noise characteristics of spiral bevel gears.

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]

Copyright of China Mechanical Engineering is the property of Editorial Board of China Mechanical Engineering 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 Lubrication Engineering (0254-0150) is the property of Editorial Office of LUBRICATION ENGINEERING 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 Lubrication Engineering (0254-0150) is the property of Editorial Office of LUBRICATION ENGINEERING 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.)

Aiming at the problems of lap spacing optimization for ER120S-G high-strength steel based on wire and arc additive manufacturing process, the pulsed gas metal arc welding (GMAW-P) processes were adopted to perform Canny edge extraction and Gaussian smoothing filtering for 5 sets of single-layer weld passes, and different functions were selected to fit the single-pass morphology. Conventional lap model and optimized slant-top lap model were compared, and the optimal lap spacing of them was calculated. The results show that, the sine function fits the weld contour best in the GMAW-P process of high-strength steel, and the optimal lap spacing from the optimized slant-top lap model is as 0.66 times of the weld width. Based on the above results, multi-layer multi-pass bulk samples were fabricated, and the surface quality is good and without obvious defects. The bulk mainly contains needle ferrite, granular bainite, and M-A elements. The tensile strength is anisotropic. [ABSTRACT FROM AUTHOR]

Aiming at the problems that the micro-cutting mechanism of A-WEDM was not clear. Single-crystal silicons were used as the processing objects herein. The maximum discharge gap was measured by designing a circuit. The material removal mechanism of A-WEDM was studied by collecting and analyzing the discharge waveform, observing the surface topography of the workpieces, and comparing the height of the abrasive grain and the discharge gap. The effects of 4 factors(pulse width, duty cycle, feed speed and wire speed) on the material removal rate and surface roughness were investigated. The experimental results show that the maximum discharge gap is as 57 μm, i.e., in the initial stage of machining, discharge corrosion first occurs. When the machining is in stable stages, within each pulse width, the materials are removed under the coupling effects of discharge corrosion and diamond particle grinding. In each pulse interval, the discharge corrosion effect stops and the diamond particle grinding action still exists, thereby removing parts of the recast layer and craters. [ABSTRACT FROM AUTHOR]

The surface topography of parts serves as a crucial role for machining quality. In order to achieve accurately prediction of the surface topography of precision milling, a surface topography simulation method based on wavelet packet analysis and frequency spectrum analysis of cutting vibration is proposed in this paper. In the paper, firstly, the ball-end milling is taken as the research object and the motion trace model of cutting edge changing with time based on the workpiece coordinate system is established. And then the vibration equation obtained by wavelet packet analysis and spectrum analysis is put into the model. Finally, the surface topography of the part is simulated and predicted by employing MATLAB. The comparisons between simulation and trial experiments suggest that the accuracy of the surface topography simulation prediction model based on wavelet packet analysis and frequency spectrum analysis of vibration signal offers a reference for the actual processing and production.

Copyright of Lubrication Engineering (0254-0150) is the property of Editorial Office of LUBRICATION ENGINEERING 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.)

To analyze the influences of surfaces topography on the laser damage and performance of KH2PO4 (KDP) crystal, the frequency features of machined surface KDP crystal surfaces were extracted and reconstructed by power spectral density and continuous wavelet transform. Wave optics theory was used to analyze the influences of frequency features on the subsurface light temperature fields of KDP crystals irradiated by 1.064 µm laser wavelength with the power of 20 MW/µm² for Ins. The results show that temperature of KDP crystals becomes larger with wavelength of surface frequencies closer to incident laser wavelength(1.064 µm). If the wavelength is over 20 µm, temperature of KDP crystals is unchanged with the changing of frequency features. The obvious wavelengths on the machined surface of KDP crystals obtained by cutting experiments are as 14 µm, 50 µm and 140 µm respectively, and the subsurface temperature of KDP crystal affected by these frequency features rises are as 56K, 22K and 12K. Maximum temperature of KDP crystals Increases with the increasing of amplitude under the same wavelength. With the increasing of surface frequency wavelength, the positon of the maximum temperature extends to the interior of the KDP crystals. [ABSTRACT FROM AUTHOR]

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Copyright of China Mechanical Engineering is the property of Editorial Board of China Mechanical Engineering 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 Lubrication Engineering (0254-0150) is the property of Editorial Office of LUBRICATION ENGINEERING 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 Journal of Architecture & Civil Engineering is the property of Chang'an Daxue Zazhishe 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.)

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Superficial cartilage defect is an important factor that causes osteoarthritis. Therefore, it is very important to investigate the influence of superficial cartilage defects on its surface morphology and mechanical properties. In this study, the knee joint cartilage samples of adult pig were prepared, which were treated by enzymolysis with chymotrypsin and physical removal with electric friction pen, respectively. Normal cartilage and surface treated cartilage were divided into five groups: control group (normal cartilage group), chymotrypsin immersion group, chymotrypsin wiping group, removal 10% group with electric friction pen, and removal 20% group with electric friction pen. The surface morphology and structure of five groups of samples were characterized by laser spectrum confocal microscopy and environmental field scanning electron microscopy, and the mechanical properties of each group of samples were evaluated by tensile tests. The results show that the surface arithmetic mean height and fracture strength of the control group were the smallest, and the fracture strain was the largest. The surface arithmetic mean height and fracture strength of the removal 20% group with electric friction pen were the largest, and the fracture strain was the smallest. The surface arithmetic mean height, fracture strength and fracture strain values of the other three groups were all between the above two groups, but the surface arithmetic mean height and fracture strength of the removal 10% group with electric friction pen, the chymotrypsin wiping group and the chymotrypsin soaking group decreased successively, and the fracture strain increased successively. In addition, we carried out a study on the elastic modulus of different groups, and the results showed that the elastic modulus of the control group was the smallest, and the elastic modulus of the removal 20% group with electric friction pen was the largest. The above study revealed that the defect of the superficial area of cartilage changed its surface morphology and structure, and reduced its mechanical properties. The research results are of great significance for the prevention and repair of cartilage injury.

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]

Copyright of Bearing is the property of Bearing 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.)