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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.)

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.