A model of a micro-texture tool featuring various textures such as micro-pits, parallel grooves, vertical grooves, and oblique grooves was developed. The impact of these micro-texture tools on the turning process of titanium alloy was investigated using the finite element analysis software ABAQUS. Through an examination of cutting force, friction coefficient, cutting temperature, and surface residual stress for micro-texture tools with distinct morphologies, the optimal micro-texture morphology was determined. The findings reveal that micro-texture tools can effectively reduce the cutting force, friction coefficient, and cutting temperature while transforming surface residual stress from tensile to compressive on the workpiece. Furthermore, with increasing cutting speed, cutting force and cutting temperature rises, friction coefficient decrease, and the residual stress on the workpiece surface shifts from compressive to tensile stress, exhibiting an ascending trend.

In the process of processing GH4169 nickel?based superalloy, serious work hardening would occur, as well as difficult machining problems caused by excessive cutting force. The finite element model of two?dimensional orthogonal turning was established by ABAQUS software. The influence of cutting speed and amplitude on cutting force and the change of tool path of GH4169 ultrasonic elliptical vibration turning were analyzed. The results were compared with those of ordinary turning process. The results show that the cutting process parameters in the ultrasonic elliptical vibration turning of nickel?based superalloys have a significant effect on the cutting force. Choosing reasonable process parameters can effectively reduce the cutting force and improve the machining quality.

Finite element analysis software ABAQUS was used to study the process of micro texture PCBN tool turning Cr12MoV, Taguchi method was used to carry out orthogonal experimental design. The variation law of the actual contact area between tool and chip, cutting force and cutting temperature with texture parameters was studied by signal?to?noise ratio analysis method, and the optimal combination of texture parameters was obtained. The results indicate that the actual tool?chip contact area decreases with the increase of texture groove width and texture edge pitch respectively. Texture groove width and texture edge pitch have the most significant influence on cutting performance of the tool; Compared with the non?textured tool, the micro?textured PCBN tool with the optimal texture parameter combination can reduce the cutting force by 5.2% and the cutting temperature by 4.7%.

With the rapid economic development, the demand for energy continues to increase, and the emission of CO₂ gas keep growing. The electrochemical reduction of carbon dioxide (ERC) to fuel and chemicals is an effective way to realize the conversion and utilization of CO₂ as well as the storage of renewable energy. Cu?based catalysts are one of the materials which can directly reduce CO₂ to high value?added chemicals(such as hydrocarbons) with high efficiency. Thus, the Cu?based catalysts have been one of the research focus of ERC technology research. The main research progress of Cu?based catalysts for ERC technology in recent years is reviewed. Firstly, reaction principle of ERC and the technology challenge are summarized, and then the cooperative control strategy for the structure and composition of copper?based catalysts is discussed for monometallic copper?based catalysts, polymetallic copper?based catalysts, copper oxide and oxide?derived copper catalysts, and copper?organic composite catalysts. In addition, research progress and unsolved problems of Cu?based catalysts are also summarized. Finally, the future trend these catalysts is also prospected.