HTM ›› 2020, Vol. 45 ›› Issue (2): 197-201.DOI: 10.13251/j.issn.0254-6051.2020.02.038

Previous Articles     Next Articles

Effect of aging process on tensile and high temperature compressive properties of 25Cr-20Ni-2.5Al high strength heat-resistant steel

Gao Shasha1, Sun Yuzhu2   

  1. 1. Department of Mechanical and Electrical Engineering, City University of Zhengzhou, Zhengzhou Henan 452370, China;
    2. School of Mechanical Engineering, Henan Polytechnic Institute, Nanyang Henan 473000, China
  • Received:2019-08-26 Online:2020-02-25 Published:2020-04-03

Abstract:

25Cr-20Ni-2.5Al heat resistant steel was prepared by adding 2.5% Al in 25Cr-20Ni heat-resistant steel and its mechanical properties were characterized and analyzed by means of tensile and high temperature compression experiments, respectively. The results show that the tensile strength of the sample after 36 h aging treatment is significantly improved, and the tensile strength and elongation are 803 MPa and 27.1%, respectively. After 36 h aging treatment, the toughness of the tensile fracture is reduced and the traces of partial brittle fracture are generated. With the aging temperature increasing, the tensile strength of the heat-resistant steel increases first and then decreases, while the elongation decreases first and then increases. The turning point occurs at the aging temperature of 650 ℃, when the tensile strength and elongation are 451 MPa and 10.26%, respectively. When the deformation degree increases, the grain reaches a larger deformation extent, while the grain size of the heat-resistant steel does not change obviously after thermal compression treatment. Precipitation phase also exists at the grain boundary, and the number of precipitation phase increases slightly when the deformation increases.

Key words: 25Cr-20Ni-2.5Al high strength heat-resistant steel, aging treatment, tensile, compression

CLC Number: