Effect of Pre-deformation on Nanoscale Precipitation and Hardness of a Maraging Stainless Steel

作者：Zhou, Xinlei; Wang, Bin; Zeng, Tianyi; Yan, Wei^*; Luan, Junhua; Wang, Wei; Yang, Ke; Jiao, Zengbao

来源：Acta Metallurgica Sinica-English Letters, 2022, 35(12): 2089-2100.

DOI：10.1007/s40195-022-01440-4

• Maraging stainless steel
• Pre-deformation
• Precipitation hardening
• Atom probe tomography

The effect of pre-deformation on nanoscale precipitates and hardness of a maraging stainless steel strengthened by the co-precipitation of Ni3Ti, Mo-enriched and Cr-enriched precipitates was systematically studied using electron back scattered diffraction, transmission electron microscopy and atom probe tomography (APT). Hardness measurements showed that the hardness of specimen with a deformation ratio of 90% peaked at HV 718 aged for 24 h, which is higher than that in the undeformed specimen (HV 603) aged for 72 h at 480 degrees C. APT characterization revealed that pre-deformation could shorten the incubation time of the Mo-enriched and Cr-enriched precipitates. At the early-aged stage, pre-deformation increased the stain energy that inhibited the nucleation of Ni3Ti precipitates, but accelerated the rejection of Mo from Ni-Ti clusters. Besides, the strengthening model indicated that strain hardening (43%) makes a larger contribution to the hardness at the early-aged condition, while precipitation hardening (58%) has most contribution to the hardness at the peak-aged conditition.

• 单位
  郑州大学; 中国科学院