Microstructure and properties of powder metallurgy martensitic-austenitic composite steel
LI Jingyu1，2，WANG Yaomin2，JIANG Feng2，LI Yanguo3，YANG Zhinan2,3，ZHANG Fucheng3
（1.Crrc Tangshan Co., Ltd., Tangshan 063000, Tangshan 063000, China;2. National Engineering Research Center
for Equipment and Technology of Cold Strip Rolling, Yanshan University, Qinhuangdao 066004, China;3. State
Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004, China）
Abstract：In recent years, the demand for high-strength-high-plasticity metal materials in the fields of automobiles
and ships has been increasing. In order to obtain high-strength-high-plasticity metal materials, powder metallurgy
technology plays an increasingly important role. In this study, the mixed metal powders of martensitic steel and
austenitic steel with a mass ratio of 2:1 were sintered by spark plasma sintering (SPS), and the austenite phase was
uniformly distributed in the martensite phase. The density of the sample is as high as 95.5%, and through the subsequent
hot rolling treatment, the sintering quality of the composite steel is improved, and the density is increased to
98.9%.The yield strength, tensile strength, uniform elongation and total elongation of the clad steel after hot rolling
are 960 MPa, 1 529 MPa, 6.7% and 6.7%, respectively. On the basis of hot rolling, cold rolling + short-time high
temperature tempering treatment is introduced, and the performance of powder metallurgy composite steel is further
improved. Among them, the clad steel cold-rolled at 30%-500℃ and tempered for 5 min has yield strength,
tensile strength, uniform elongation and total elongation of 1 899 MPa, 1 964 MPa, 9.2% and 10.0%, respectively.
2023, Vol. 33 
