Reseach On Microstructure And Properties Of High Strength And High Conductivity Copper Alloy Used In Roll

In this dissertation,the effects of different aging treatments and alloying elements Cr,Zr,Ni,Be,Co on the microstructure and properties of Cu alloys were investigated by means of hardness test,conductivity test,OM and SEM.Use other elements to replace or reduce toxic beryllium elements,which is used in roll Study the method of adding nano-Y2O3 in casting pure copper.The results show that:(1)After 950?/2h solution and 450?/4h aging of the Cu-1.22Cr-0.30Zr alloy,most of the Cr precipitate in the form of spheres,while Zr and Cu form metal compounds Cu3Zr and Cu5Zr.A small amount of Zr form metallic compounds around the spherical Cr-rich phase with the element of Cu and Cr.(2)The optimum aging treatment system of the Cu-1.22Cr-0.30Zr alloy is aging at 450?/4h,the hardness and electrical conductivity is 120HB,67.3%IACS respectively.(3)The effect of Zr on the hardness of Cu-Cr-Zr alloy is greater than that of Cr and Ni,and only changing the content of Cr and Zr or adding Ni can't satisfy the requirement of hardness of the roll.(4)The addition of Be and Co can significantly improve the hardness of the copper alloy,but will reduce the conductivity,The hardness of Cu-0.30Zr-1.00Ni0.36Be-0.26Co alloy after solution treatment at 950?/2h+450?/4h aging treatment is 232HB,which reach the hardness of the roll.The conductivity is 53.6%IACS,which close to the conductivity requirements of the roll.Cu-Zr-Ni-Be-Co alloy is the most promising copper alloy that can reach the performance of the roll.(5)The addition of Y2O3 can significantly improve the hardness of Cu-Y2O3 composite,the hardness is proportional to the content of Y2O3.The combination of powder metallurgy and casting method to make nano-Y2O3 dispersed in copper is still a certain degree of difficulty.