Acta Metallurgica Sinica (English Letters) ›› 2019, Vol. 32 ›› Issue (1): 116-126.DOI: 10.1007/s40195-018-0837-y

Special Issue: 2018-2019高温合金专辑 2019年腐蚀专辑-2

• Orginal Article • Previous Articles     Next Articles

Effect of Heat Treatment on Microstructure and Stress Rupture Properties of a Ni-Mo-Cr-Fe Base Corrosion-Resistant Superalloy

Tao Liu1, Mei Yang1, Jun-Song Wang2, Jia-Sheng Dong3(), Li Wang3(), Lang-Hong Lou3   

  1. 1.Jiangsu University of Technology, Changzhou 213001, China
    2.Harbin Engineering University, Harbin 150001, China
    3.Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China
  • Received:2018-07-09 Revised:2018-09-01 Online:2019-01-20 Published:2019-01-18
  • Contact: Dong Jia-Sheng,Wang Li
  • About author:

    Author brief introduction:Dao-Kui Xu Professor of IMR, CAS, and “Young Merit Scholar” of Corrosion Center in the Institute of Metal Research (IMR), Chinese Academy of Sciences (CAS). He achieved Ph.D. degree from IMR, CAS, in 2008, during which he obtained “Chinese Academy of Sciences-BHP Billiton” Scholarship award, “Shi Changxu” Scholarship award and “Zhu-LiYueHua” Excellent Doctorate Student Scholarship of Chinese Academy of Sciences. He worked as a Research Fellow in ARC Center of Excellence, Design of Light Metals, Department of Materials Engineering, Monash University, Australia (2008.10-2011.10). He published more than 60 peer-reviewed scientific papers, attended 20 invited lectures and holds seven patents. His papers were cited more than 1200 times. His research interests mainly include: (1) fatigue behavior and fracture toughness of light metals, such as Mg, Al and Ti alloys; (2) effects of alloying, heat treatment and thermomechanical processes on the microstructural evolution and mechanical improvement of light metals; (3) corrosion, stress corrosion cracking and corrosion fatigue behavior of lightweight alloys; and (4) design of new lightweight alloys with a good balance of properties in terms of mechanical property and corrosion resistance.

Abstract:

The influences of heat treatment and test condition on the microstructure and stress rupture properties of a Ni-Mo-Cr-Fe base corrosion-resistant superalloy have been investigated in this paper. Optical microscope and scanning electron microscope were employed for the microstructure observation, and X-ray diffraction, electron probe micro-analyzer, and transmission electron microscope were used for phase determination. It was found that the grain size increased and the volume fractions of initial M6C carbides decreased along with the increase in solution treatment temperature. When tested at 650 °C/320 MPa, the stress rupture lives decreased with the increase in solution treatment temperature, but the stress rupture lives increased slightly at first and then decreased for the samples solution heat treated at 1220 °C when tested at 700 °C/240 MPa. The elongations showed the descendent trends under these two conditions. The stress rupture life and elongation for the aged samples all showed a noticeable improvement at 650 °C/320 MPa, but there was no noticeable improvement at 700 °C/240 MPa. The reasons can be attributed to the grain size, test conditions, and the initial and secondary carbides.

Key words: Corrosion-resistant superalloy, Heat treatment, Stress rupture properties, Secondary carbides