Heat Treatment of Metals ›› 2022, Vol. 47 ›› Issue (6): 98-102.DOI: 10.13251/j.issn.0254-6051.2022.06.018

• PROCESS RESEARCH • Previous Articles     Next Articles

Effect of quenching oil temperature on microstructure and properties of 40CrMnMo steel drill pipe

Zhong Bin1,2, Chen Yiqing1,2, Li Lin1,2, Gao Peng1,2, San Hongyu1,2, Ai Fangfang1,2, Tian Xiumei1,2   

  1. 1. State Key Laboratory of Metal Material for Marine Equipment and Application, Anshan Liaoning 114009, China;
    2. Ansteel Iron & Steel Research Institute, Anshan Liaoning 114009, China
  • Received:2022-01-18 Revised:2022-04-20 Online:2022-06-25 Published:2022-07-05

Abstract: Effect of quenching oil temperature on microstructure and cross-section hardness of the quenched 40CrMnMo steel drill pipe, the mechanical properties and the impact absorbed energy of the tempered state was studied by means of hardness test, microstructure observation, tensile property and impact property test. The results show that the quenching oil temperature has a significant effect on microstructure and hardness of the drill pipe, and further affects the mechanical properties, yield ratio and impact absorbed energy after tempering. With the increase of quenching oil temperature, the cooling rate increases firstly and then decreases, the optimum medium temperature is 30-50 ℃, at which the specimen has good hardenability, uniform microstructure and fine grains. After tempering, the specimen has good mechanical properties, high yield ratio, high impact property and good toughness, and good comprehensive property.

Key words: quenching oil temperature, 40CrMnMo steel drill pipe, microstructure, properties

CLC Number: