Heat Treatment of 317L 1.4438 Stainless Steel

The austenitic stainless steel pipe are provided in the mill annealed condition ready for use. Heat treatment may be necessary during or after fabrication to remove the effects of cold forming or to dissolve precipitated chromium carbides resulting from thermal exposures. For the Alloys 316 and 317L the solution anneal is accomplished by heating in the 1900 to 2150°F (1040 to 1175°C) temperature range followed by air cooling or a water quench, depending on section thickness.

Cooling should be sufficiently rapid through the 1500 to 800°F (816 to 427°C) range to avoid reprecipitation of chromium carbides and provide optimum corrosion resistance. In every case, the metal should be cooled from the annealing temperature to black heat in less than three minutes.

Forging
The recommended initial temperature range is 2100-2200°F (1150-1205°C) with a finishing range of 1700-1750°F (927-955°C).

Annealing
317LMN and Alloy 317L stainless steel can be annealed in the temperature range 1975-2150°F (1080-1175°C) followed by an air cool or water quench, depending on thickness. Plates should be annealed between 2100°F (1150°C) and 2150°F (1175°C). The metal should be cooled from the annealing temperature (from red/white to black) in less than three minutes.

Hardenability
These grades are not hardenable by heat treatment.

Alloys 316 and 317L stainless steel tube cannot be hardened by heat treatment.

SA 213 TP 317L