The Microstructure Evolution Of Severe Plastic Deformation By Multiple Forging And Rolling On Pure Aluminium

As one kind of key sputtering target material for producing semiconductor chip and TFT-LCD, the high purity aluminum is more and more important in high and new technologies. The quality of the semiconductor chip and TFT-LCD are determined by the high purity aluminum target. The purity and the grains size are the main qualification of the high purity aluminum target. The purpose of this paper is to investigate the effect of multiple forging and rolling on the structures of high purity aluminum, which will provide a technical support for the high purity aluminum target production. In addition, in order to study the influence of Severe Plastic Deformation(SPD) process on the structure and performance of commercial pure aluminum, first, we did multiple forging simulation by DEFORM, then did multiple forging and rolling experiments, and also achieved good effect.The experiment includes three parts:(1) Study on the influence of structure and performance of high purity aluminum by multiple forging and rolling, and do heat treatment on deformed samples, through the macrotructure, microstructure and hardness of analysis, to select the best forging, rolling and heat treatment process.(2) Industrial pure aluminum multiple forging simulation by DEFORM, simulation of different forging temperature,different multiple forging passes and the different back furnace heating system when hot multiple forging, analysis on mesh damage, temperature field and stress-effective.(3) On the basis of simulation, we study on the influence of structure and performance of industry pure aluminum by multiple forging and rolling, did different temperature annealing treatment on samples after rolling, researched the recrystallization process.Experimental results show that:(1) When high purity aluminum to multiple forging,the specimen is heated to between260℃-350℃, multiple forged12passes, the end of forging temperature controlled around65℃, we can get ideal structure.(2) Through the experim ents, DEFORM simulation conforms to experimental results.(3) Industrial pure aluminum heated to about400℃, multiple forged12passes then rolled pass degree of reduction is10%, the total degree of reduction for80%, last,340℃for1.5h annealing of the samples after rolling, we can get small, uniformly distributed equiaxed grains.