CHANGES IN MICROSTRUCTURE AND HARDNESS DURING PROPERZI PROCESS OF 6151 ALUMINUM ALLOY WIRE ROD FOR FORGING

摘要

Deformation behaviors during Properzi process consisting of continuous casting and 6 steps of rollings in 6151 aluminum alloy for forging, were investigated by means of microscopy and hardness measurement. Original grain size in as cast bar decreases with increasing total area reduction and reaches to 15 ～ 20μm with homogeneous distribution through out the transverse section of rolled rods after the 6th rolling. Fine grains with the size of 2 ～ 10μm are formed within the original grains after each rolling. Remarkable softening occurs in all over the section after the 2nd rolling, total area reduction;56%, and work hardening proceeds gradually during the 3rd, 4th, 5th and 6th rolling. Above mentioned changes in microstructure and hardness during Properzi process results in good workability of 6151 aluminum alloy wire rod.