Effect Of Cold-rolled Processing Parameters On Deep-drawing Performance Of Micro-carbon Steel

Micro-carbon steel is widely used in deep-drawing parts, and has a great demand especially in automobile industry field. Micro-carbon steel is evolved from the traditional basis of low-carbon Al-killed steel. Micro-carbon steel in the ferritic rolling can improve the deep-drawing performance through cold rolling and annealing.Chemical composition of micro-carbon steel is usually a kind of low-carbon, low sulfur, and a good deep-drawing performance, and produces important deep drawing parts. Billet hot-rolled in the ferritic rolling, through cold rolling with different reduction ratio and different temperature annealing, has won cold-rolled reduction ratio and annealing temperature on influence of the deep-drawing performance. Under different process conditions, rolled samples were tensile tested, the detection of r value, texture text and microstructure observations, combined with a quantitative ODF and microstructure analysis, the relationship between the deep-drawing properties and process parameters were studied.Through laboratory rolling and performance testing, conclusions are as follows:Cold rolling reduction rate has a greater impact on the recrystallization grain's size, the greater the degree of cold deformation, the more fine crystalline grains. In 90% of the cold rolling reduction ratio, after 750℃annealing grain's size is about 20μm.The organization has a certain amount of {111}//ND component,which is used ferritic hot rolling. After 90% cold rolling reduction and the subsequent annealing process can get the strongest {112}<110>and {111}//ND recrystallization texture, and annealling at 750℃annealing conditions the r value increases around 0.3 more than 700℃.As the annealling temperature increases, r value is also significantly improved. In the same cold rolling reduction rate, annealling at 750℃annealing conditions, r values can increase on average by about 25% more than 700℃.In production of micro-carbon steel, production and technological improvements in theory have always been the hotspot of our corporate researches, Test obtained relations with the deep-drawing properties and parameters can provide theoretical guidance for the actual production.