Affiliation:
1. The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and Technology 947 Heping Avenue Wuhan 430081 P. R. China
2. Technical Center Hunan Valin Lianyuan Iron and Steel Co., Ltd. 1005 North Gangui Road Louxing District Loudi 417009 P. R. China
Abstract
High‐strength steels with low carbon content have low stress relaxation during tempering and are prone to distortion during processing. To improve tempering stress relaxation, 10% compression predeformation is introduced. Carbide precipitation is characterized by dislocation density and dilatometry curves, and the evolution of residual stress during tempering is investigated. The results show that predeformation can inhibit cementite precipitation, increase the effective carbon concentration in the ferrite matrix, and induce the diffuse precipitation of alloy carbides. The dispersed alloy carbides provide more interfaces for Mn partitioning, strengthen the transformation plasticity, and enhance the stress relaxation. After tempering at 700 °C for 30 min, the average residual stress and the elastic strain energy of undeformed/predeformed specimens are 39.18/13.25 MPa and 25.40%/90.92%, respectively.
Subject
Materials Chemistry,Metals and Alloys,Physical and Theoretical Chemistry,Condensed Matter Physics