Simulation And Experimental Study On Mechanism Of Micro Cutting Vit1 Amorphous Alloy

As a kind of new material prepared by rapid condensation technology,amorphous alloy has many excellent properties due to its lack of crystal structure.And as result its unique microstructure also leads to some defects such as brittleness at room temperature and temperature sensitivity.Besides,it is difficult to produce large size blanks,which greatly limits its application.The wide prospect of amorphous alloys in micro devices makes it important to study the micro-cutting mechanism of amorphous alloys.The cutting characteristics of amorphous alloys are significantly different from those of crystalline materials at conventional cutting scales,and many unique phenomena appear with the reduction of cutting scales.It has great value to have an in-depth study of the cutting mechanism of amorphous alloy materials under micro-cutting conditions,which make great sense to improve of the cutting technology of amorphous alloy and to identify the mechanical properties and deformation mechanism of amorphous alloy at micro scale.In this paper,VIT1 type amorphous alloy is taken as the research object.Through the combination of simulation and experiment,the following aspects are mainly studied:The finite element simulation micro cutting model of Vit1 amorphous alloy was established.The thermal distribution and cutting force curve of amorphous alloy under the condition of micro cutting were identified.And the influence of cutting parameters on temperature and cutting force were explored.By combination of theoretical calculation and simulation,the minimum cutting thickness of amorphous alloy will be investigate.The removal process of micro cutting amorphous alloy will be investigated by analyzing the simulation result of cutting heat,cutting force and chip formation characteristics.By building a micro-milling experiment platform and taking VIT1 amorphous alloy as the machining object,cutting forces were collected after micro-milling experiment on a precision micro-milling machine.The characteristics of original cutting force curves were analyzed.Through orthogonal experiment the significant degree of influence of cutting parameters on cutting force were studied,and the empirical formula of cutting force in micro-milling of amorphous alloy will be established.By discussing the influence law of cutting parameters on cutting force in single factor experiment,and combining with the cutting conditions in which the cutting phenomenon changes obviously,the critical conditions for the change of removing mechanism in the cutting process was explored.The chip collected from the microgrooves and the tool used in the micromilling experiment were observed to study the surface formation process of amorphous alloy and analyze the material removal mechanism.Surface roughness were measured and the influence of cutting parameters on roughness and the optimal process combination will be studied.The temperature change and surface formation process of the amorphous alloy during cutting will be analyzed by the image of the machined surface.The chip morphology characteristics obtained from the conventional chip and micro-milling will be compared and analyzed,and whether the brittle-plastic transformation occurred and whether the material was removed in a plastic way under the micro-cutting condition will be identified.The mechanism of tool wears will be inferred from the microscopic appearance of tool.By using of scanning electron microscopy(SEM),burr and machined surface microstructure were observed.The temperature changes in the process of micro-milling amorphous alloy and the surface and into the process were studied.By comparing the micro morphology of conventional chip and micro milling chip,and analyzing the characteristics of micro milling chip morphology whether brittle-ductile transition took place in the micro cutting conditions and whether material removed in the plastic way were defined.