| Rapid wear of the tool is still the key issues for high speed machining of difficult-to-cut materials.It is difficult to further enhance the cutting speed of difficult-to-cut materials before perfectcombination of high hardness and toughness of circumstances ceramics and superhard materials.Cemented carbide are mainly used for titanium alloy and it is an effective way to increase themachining efficiency of titanium alloy by improving frictional contact state of tool/workpiece toreduce cutting force, cutting temperature and tool wear. Currently biomimetic tribology study arefound that high-performance surface texture has the effects of good anti-friction, anti-adhesion andimproving the wear resistance, which gives a new research direction that surface texture will beapplied to the surface of cutting tool. In this paper, aiming at friction and wear problems in theprocessing of titanium alloy, the exploratory research was conducted on the application of surfacemicro-textured cutting tool for titanium alloy. The major works are included as follows:(1) The cutting tests for the traditional tools were carried out under the cooling and lubricatingconditions, such as dry cutting, cold air, MQL, cryogenic MQL, static environment, and the influenceof cooling/lubricating medium on friction states and tool wear of high-speed machining of titaniumalloy were studied. Combined with cutting physical simulation experiment, the action mechanism ofcooling/lubricating medium in the friction process of tool/workpiece friction pair was analyzed.(2) The design and manufacturing technology of the tool surface micro-texture was studied. Byfinite element analysis the influence of micro-pit/groove parameters on the tool surface stress anddeformation was analyzed, which guided the design of the tool surface micro-pit/groove. The surfacemicro-textures were processed using laser machining and electrochemical machining technology, andadvantages and disadvantages of the two processing techniques were comparative analyzed, whichprovided a reference value for manufacturing technology of the tool surface micro-texture.(3) Friction and wear test of Ti6Al4V/WC-Co were carried out by comparison with traditionalsmooth surface, and anti-friction properties of micro-textured surface were studied. Test resultsshowed that micro-texture could effectively reduce the friction coefficient of friction pair. Theinfluence of micro-pit diameter on the friction coefficient was greater than micro-pit depth, andmicro-groove had better anti-friction effect than the micro-pit.(4) The orthogonal cutting tests were conducted for the surface micro-textured cutting tool, and thecutting forces and cutting temperatures were measured. The results showed that both the micro-pitsand micro-grooves could effectively reduce the cutting force and cutting temperature under lubricantcondition, and texture types had a greater impact on the cutting performace of tools. Finite elementmodel of orthogonal cutting titanium alloy with surface micro-textured cutting tool was created, andsimulation results showed that the micro-grooves could extend the tool/chip contact length, increasecutting force while widen the heat transfer surface area of the tool, decrease the cutting deformation,thus reduce the cutting temperature. The chip morphologies of titanium alloy were observed and theimpact of micro-grooves on the chip formation was analyzed.(5) Turning tests with surface micro-textured cutting tool were carried out and the results showedthat the surface micro-grooved cutting tool had higher tool life than the traditional smooth surfacecutting tool. In dry, MQL and cryogenic MQL conditions, micro-grooved cutting tool decreased theaverage flank wear of5.0%,7.7%,12.3%. Wear and damage mechanism of surface micro-grooved cutting tool was analyzed. It was found that surface micro-grooves could reduce adhesion wear of tooland cemented carbide between micro-grooves would damage in the action of adhesion and impact ofchip.
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