Stress Relieving Heat Treatment
This heating processes, typically done in an open atmosphere furnace at 1200F, is used to remove stresses in welded steels or cast iron so that distortion will not occur when components are machined or subsequently heat treated. This temperature is lower than the annealing process so there is less component distortion. Stress relieving, at a lower temperature, also occurs in the nitriding process due to the long soak time required for the nitriding process. Automotive castings that have been repaired with stainless steel welding alloys typically require stress relieving to prevent cracking around repaired valve seat cracks.