Effect of Intercritical Annealing Time on the Microstructures and Tensile Properties of a High Strength TRIP Steel  

作　　者：Chao Wang Hua Ding Jun Zhang Hongyan Wu 

机构地区：[1]School of Materials and Metallurgy, Northeastern University [2]State Key Laboratory of Rolling and Automation, Northeastern University

出　　处：《Acta Metallurgica Sinica(English Letters)》2014年第3期457-463,共7页金属学报（英文版）

基　　金：supported by the National Natural Science Foundation of China (No. 51031001)

摘　　要：A new Mn-Si-Al-Mo-Nb transformation-induced plasticity steel was annealed by intercritical annealing for different durations to investigate the partitioning of C element and the volume fraction change of the microstructural constituents. Direct experimental evidence confirms the partitioning of C elements in different phases during heat treatment by Electron probe microanalysis and X ray diffraction. The distribution of the precipitates was investigated as well. It was revealed that the microstructures and mechanical properties of the investigated steels were affected by the intercritical annealing time. According to the present experiment, the volume fraction of retained austenite and the product of tensile strength and total elongation of investigated steel decrease with increasing intercritical annealing time. It was observed that high tensile strength of 1,103 MPa, total elongation of 21.3%, and strength-ductility product of 23,493.9 MPa % could be successfully produced in this experimental steel at intercritical annealing temperature of 830 ℃, holding for 1 min, and isothermal bainite treatment of 440 ℃ for 5 min holding time.A new Mn-Si-Al-Mo-Nb transformation-induced plasticity steel was annealed by intercritical annealing for different durations to investigate the partitioning of C element and the volume fraction change of the microstructural constituents. Direct experimental evidence confirms the partitioning of C elements in different phases during heat treatment by Electron probe microanalysis and X ray diffraction. The distribution of the precipitates was investigated as well. It was revealed that the microstructures and mechanical properties of the investigated steels were affected by the intercritical annealing time. According to the present experiment, the volume fraction of retained austenite and the product of tensile strength and total elongation of investigated steel decrease with increasing intercritical annealing time. It was observed that high tensile strength of 1,103 MPa, total elongation of 21.3%, and strength-ductility product of 23,493.9 MPa % could be successfully produced in this experimental steel at intercritical annealing temperature of 830 ℃, holding for 1 min, and isothermal bainite treatment of 440 ℃ for 5 min holding time.

关 键 词：TRIP steel Intercritical annealing Carbon partitioning Retained austenite STABILITY 

分 类 号：TG142.1[一般工业技术—材料科学与工程]