Research About Preparation Technology And Solidification Structure Of Cu-Cr Alloy With High Component Of Cr

Because of favourable properties like high strength and hardness,great electrical and thermal conductivity,grateful resistance to corrosion,Cu-Cr alloy is widely used in a variety of territories.Cu-Cr alloy with a high component of chrome is widely used in the piezoelectric contact materials.Because of the low compatibility Cu-Cr alloy,it’s difficult to produce Cu-Cr alloy.Cu-Cr alloy with a component of Cr ranging from 10 wt.% to 25 wt.% was prepared by vaccum induction melting in marmag crucible.Research about the effect of different technological parameters on the microstructure of Cu-Cr alloy was done by metallographic analysis.Simultaneously,numerical simulation of the solidification process was done by using Finite Element Method,Finite Difference Method and Dissipative Particle Dynamics in order to explaint the segregation mechanism of the Cr-rich phase.At the same time,quantitative analysis about the degree of Cr-rich phase’s segregation was done.Finally,analysis about the specific problem emerging in process of producing Cu-25%wtCr alloy was done by comparing the results in research.Simultaneouly,samples were prepared by vaccuum arc melting to serve as the reference substance with ideal solidification structure.Comparision among samples’ solidification structure prepared by the two technology was done to analyze the advantages and drawback of the two technologys.Using the advantages of vaccuum arc melting,the mechanism of Cr-rich phase’s migration was learned more deeply.After compreshensivly analyzing,it was found that:(1)With the cooling rate going down,the degree of Cr-rich phase’s segregation becomesmore serious.On suitble thermodynamic conditions,serious macrosegregations takes place.(2)With the increase of the component of chrome,the degree of Cr-rich phase’s segregation becomes more serious which is affected by thermodynamic probability.(3)The degree of Cr-rich phase’s segregation,to a great extent,is affected by the solute’s diffusion’s situation.When the chrome’s diffusion isn’t sufficient.Cr-rich phase tend to distribute in a gradient.