During friction and wear, the friction coefficient of cemented carbide could be significantly reduced through surface texturing. In this work, we conducted a comparative analysis of the friction and wear resistance of the micro-textured surface and lubricated micro-textured surface and analysed the lubrication mechanism of the micro-textured surface with the solid lubrication. In particular, the effect of the micro-texture size on the friction coefficient was assessed, implying that the friction coefficient curve of the textured surface is more stable than that of the nontextured surface. In addition, the lubricated surface with the microtexture exhibited a minimum friction coefficient, which was only ∼0.25 of that of the nonlubricated surface. Micro-pits texture could store a certain amount of the lubricating agent, eventually reducing the friction coefficient. The diameter of the micro-pits texture, friction coefficient, texture depth, and texture spacing increased within the selected parameter range, the friction coefficient first decreased and then increased.

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When milling titanium alloy, the cutting temperature has a strong impact on the degree of tool wear and, in turn, tool life and the surface quality of the workpiece. The distribution of the temperature field on a tool’s rake face can be improved through the use of micro-textures, which help to reduce friction and, ultimately, wear on the tool. In this paper we present a new way to measure cutting temperature and examine heat distribution when milling titanium alloy with micro-textured ball-end milling tools. We first establish the heat flux density function for the contact area between the workpiece and the tool and then for the rest of the tool. Thermal stress simulation shows that adhesive wear tends to happen in the contact area and on the flank face, rather than at the tip of the tool, with the temperature distribution gradient for the rest of the tool being more uniform. The maximum value for thermal stress on the cutting edge was 2.0782 × 106 Pa. This decrease as you move away from the cutting edge along the contact area between the tool and the workpiece. Maximum deformation of the tool is also mainly concentrated at the principal contact point, with a value of 1.9445 × 10−9 m. This, too, decreases as you move away from the cutting edge and into the rest of the contact area. This research provides the basis for the optimization of tool structure and further investigation of the thermo-mechanical coupling behavior of micro-textured ball-end milling cutters when milling titanium alloy.

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Laser surface microtexturing techniques can improve the friction properties of materials by reducing the contact area and form heat affected zones (HAZ) by energy conduction in laser processing. HAZ has a significant effect on the surface friction properties in the friction zone. This paper focuses on the formation of HAZ on the surface of cemented carbide during laser processing micro-texture. Firstly, the principle of energy absorption, conversion and conduction in laser processing is analyzed. Then the finite element method is used to study the distribution of temperature field and its change with time. Then the laser processing of microtexture of cemented carbide is carried out by laser marking machine. In the experiment, the characteristics of HAZ on the surface of cemented carbide after laser processing were studied by ultra-depth microscope, EDS and SEM. The effects of different laser processing parameters on the size of HAZ were studied, and the changes of element content after laser processing were studied. At the same time, the morphology of HAZ microcracks was observed and the reasons for its formation were analyzed. The results show that the laser power is the main factor affecting the HAZ size, followed by the laser scanning speed and the number of scans. The content of Co after laser processing is highest near the center of the micro-texture, and decreases from the center to the edge. The thermal stress and stress concentration caused by the temperature gradient cause microcracks to form around and inside the microtexture. By selecting reasonable laser parameters, it has an important influence on the size, element content and microcrack formation of HAZ, and it is of great significance to improve the micro-texture properties of the processed cemented carbide.