Experimental Investigations On Micro Grinding Characteristics And Technological Basis Of Bulk Metallic Glasses And High Entropy Alloys

In recent years,new materials have been constantly emerging and developing rapidly.The so-called new materials are new or developing materials with excellent properties and special functions that traditional materials do not have,or using new technology(technology,equipment)to improve the performance of traditional materials and produce new functions.The promotion and application of new materials to a certain extent also depend on their reasonable machining methods.With the development of machining technology,micro components have played an important role in many important fields.The application of new materials to micro components will also become a trend of development.As a special way of metal cutting,grinding is a kind of mechanical processing method to remove workpiece materials by random abrasive grains of shape and size.Grinding is one of the most widely used machining methods at present.It plays a very important role in the field of mechanical manufacturing.With the miniaturization of the parts,the machining methods have been developed and improved accordingly,thus the micro machining technology has appeared,and then the micro and nano machining technology has been developed.Micro scale grinding technology,as one of the micro machining technology,is also very important in the field of microfabrication.As a new material,amorphous bulk metallic glass(BMG)and high entropy alloy(HEA)have been developed rapidly,and their application fields are constantly expanding,and even applied in very important and critical fields.Their application and development are inseparable from mechanical processing.In this paper,the basic and exploratory experimental investigation and analysis of the grinding characteristics for Zr-based BMGs and HEAs in micro scale grinding process are carried out.The main contents of this paper are as follows:(1)In this paper,Zr-based BMGs was experimentally studied using the microscale grinding method.The dynamic signal testing system was used to collect the grinding force,and the grinding force produced during the micro scale grinding was studied by orthogonal experiment and single factor experiment.The effect degree of grinding parameters on the grinding force was obtained.The grinding force ratio of Zr based BMG under micro grinding is experimentally studied.The experimental comparison for grinding force between different processing methods,different grinding conditions,different micro grinding wheels and different workpiece materials was carried out.According to the experimental results,the grinding force of Zr based BMG accords with the theoretical model of grinding force.(2)According to the theoretical formula and empirical formula of the grinding surface roughness,the empirical formula of the surface roughness for Zr-base BMG under micro scale grinding process is obtained by the single factor experimental results of the grinding surface roughness for the Zr based BMG.The effects degree of different grinding parameters on the surface roughness of Zr-based BMG were studied.The surface roughness for Zr-based BMG of different grinding methods,different grinding conditions,different micro grinding wheels and different workpiece materials were compared.The surface topography and surface profile of Zr-based BMG were observed and analyzed.The metamorphic layer of Zr based BMG has been studied briefly,and its thickness has been measured,then its energy spectrum has been analyzed.(3)Because the high grinding temperature can cause the size and shape error of the workpiece and even the heat damage of the surface,it is necessary to control the temperature of the grinding zone during the grinding process.In the traditional grinding process,the measurement of the grinding temperature is relatively difficult to achieve.There is a large error between the collected grinding temperature and the actual grinding temperature.In the microscale grinding process,the measurement of grinding temperature will be more difficult.Therefore,the finite element simulation of the single abrasive model of Zr based BMG in the micro grinding process is first simulated,and the simulation grinding temperature is obtained.This provides an indirect basis for the study of micro scale grinding temperature of Zr-based BMG.(4)The grinding chip of Zr-based BMG produced during micro grinding process was observed and analyzed.The grinding chip morphology and shape of Zr based BMG were observed,and the material removal method was analyzed.The wear of CBN micro grinding wheel and diamond micro grinding wheel is observed and analyzed.(5)Finally,the micro grinding characteristics of the high entropy alloy developed on the basis of amorphous alloy were experimentally investigated.The research and analysis are carried out from grinding force,grinding surface roughness,grinding surface profile,grinding chip morphology,micro grinding wheel wear,grinding force simulation and grinding temperature simulation,etc.In this paper,the basic and exploratory experimental researches on the micro scale grinding characteristics of Zr-based BMG and HEA are carried out and analyzed in detail.The processing regularity and changing trend of Zr-based BMG and HEA in micro grinding process are summarized.