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This study describes the application of a magnetic abrasive finishing process (MAF) to the inner wall of the Co-Cr alloy cardiovascular tube to obtain a fine surface roughness and improve the surface quality. The high-performance spherical iron-based diamond magnetic abrasive powder (MAP) used in the experiments was prepared via combining plasma molten metal powder with sprayed abrasive powder. The experiments were carried out on a MAF machining machine for slender tubes, with permanent slotted magnets as the magnetic field-generating device. The processing mechanism of the MAF on the inner wall of the tube was analyzed, and the magnitude and distribution of the magnetic flux in the processed area were simulated by software. The material removal model for MAF processing of the inner wall of the tube was constructed from mechanical properties of magnetic abrasives and the workpiece and five applied process parameters: finishing time, tube rotational speed, magnetic feed rate, size of MAPs, and filling quantity of MAPs. Single-factor experiments were designed and carried out using surface roughness Ra and quality differences before and after MAF processing as evaluation indicators. The results were used to analyze the relationship between five process parameters and surface roughness Ra and material removal MR. Scanning electron microscopy was used to observe the effect of the MAF process on the surface quality. It shows that the MAF process can effectively remove the defective layer from the workpiece and improve its surface smoothness and quality. The surface roughness Ra of 0.46–0.49 μm before finishing was decreased to 0.093 μm with optimal process parameters. [ABSTRACT FROM AUTHOR]

In this study, a new method of ultrasonic vibration processing of high-speed EDM ultra-fine copper tube electrode is proposed, and the deformation process of copper tube during processing is simulated by finite element analysis, and a prediction model of wall thickness change of ultrasonically processed copper tube electrode is established, and the predicted values are in good agreement with the experimental measurement data. The surface quality of copper tube electrode after ultrasonic processing was improved, and the roughness was reduced from Ra1.28 to Ra0.43 µm, which is important for the automated production of high-quality ultra-fine copper tube electrode. [ABSTRACT FROM AUTHOR]

Inconel 718 offers high oxidation resistance, mechanical strength, and heat resistance, which enables turbofan engines to maintain excellent performance in an operating environment of 1000 °C. However, these properties make Inconel 718 difficult to machine with conventional machining techniques. Water-jet guided laser (WJGL) is a composite processing technology that combines water cooling and laser ablation technology, which is advantageous and promising for processing Inconel 718. While, the water layer on the substrate surface in processing limits WJGL's ability to ablate the metal, which leads to burrs formed when manufacturing groove structures. Therefore, a new method for manufacturing groove structure on Inconel 718 by annular gas-assisted water-jet guided laser (AGAWJGL) is proposed in this paper. In this study, the burr is reduced, and the material removal efficiency is improved by removing the water layer from the substrate surface with a gas-assisted. Then, groove processing experiments are performed on Inconel 718 metal plates with a thickness of 1 mm. The experimental results show that the average size of burrs reduces by 36%, and the depth of grooves increases by 13%. These provide the theoretical foundation for the WJGL machining of Inconel 718. [ABSTRACT FROM AUTHOR]