Creation of ultrafine-grained steel by high Z - large strain deformation: Bridging science and technology

摘要

Ultrafine-grained structures formed dynamically through a single-pass compression. at warm temperatures were investigated in a 0.15 percent C-0.3 percent Si-1.5 percent Mn steel. The size d (pm) of ulirafine grains surrounded by grain boundaries having a misorientation larger than 5 deg is not affected by strain and shows a constant value that satisfies the relationship of d=10~2Z~(-0.16). Ultrafine ferrite has been produced by multi-pass warm caliber rolling as a method of high Z- large strain deformation to demonstrate it as a method for bulk production. It was found that the empirical relation established as per single pass compression test is valid for multi-pass caliber rolling.