angle-left

Web Content Display

Email a friend

Heat Treating of Martensitic Stainless Steels

Editor: Jon L. Dossett, FASM, Consultant; George E. Totten, FASM, Portland State University   |   Document Download   |   Product code: ZASMHBA0005985

File size: 444 KB

Classified as: Heat Treating Materials Properties and Performance

Price: $35.00 Member Price: $30.00

The hardening of martensitic stainless steel is essentially the same as for plain-carbon or low-alloy steels, in that maximum strength and hardness depend chiefly on carbon content. There are, however, important differences stemming from the high alloy content of the stainless grades. The high alloying causes the thermal decomposition of austenite (into pearlite) to be so sluggish that austenite undergoes a thermal decomposition (into martensite). This being the case, the hardenability of martensitic stainless steel is very high. Maximum hardness is produced by air cooling in the center of sections up to approximately 300 mm (12 in.) thick, and quenching rate is not a significant issue given the high hardenability of the martensitic stainless steels. The martensitic stainless steels thus can be more sensitive to heat-treating variables than are carbon and low-alloy steels; some, especially those with higher carbon levels, may have retained austenite, which can lower hardness and cause problems with dimensional stability. The quenching rate also must be sufficient, however, to avoid precipitation of carbides in the austenite during quenching since the sensitization would persist in the final microstructure. If this occurs, a subzero treatment at below –75 C (–100 F) should be undertaken immediately after quenching.

  • From:

    ASM Handbook Volume 4D: Heat Treating of Irons and Steels

  • Publisher: ASM International
  • Published: 2014
  • Pages: 15
  • Review Type: Peer reviewed