The laser welding heat treatment do you know?
Publish Time: 2016-08-26 Origin: Site
In laser welding process of stainless steel, do you usually need to heat treatment after welding, especially the martensite and ferrite stainless steel, select the correct preheating before welding and welding post-processing is a necessary condition to ensure the quality of laser welding machine for welding.So what stainless steel heat treatment after welding process?
Heat treatment after welding of stainless steel tensile strength, creep limit and the influence of heat treatment temperature and holding time.The influence of heat treatment after welding of stainless steel impact toughness on different steel grade are different, generally stainless steel heat treatment process to choose a single high temperature tempering after welding or high temperature normalizing and tempering process:
1, high temperature normalizing and tempering
For welding joint by normalizing plus high temperature tempering heat treatment.This is because the welding seam and heat affected zone, coarse grains, the need to refine the grain, the normalizing treatment is adopted.
2, a single high temperature tempering
Single is fire cannot eliminate the residual stress, however, is required plus high temperature tempering to eliminate stress.Single medium temperature tempering is only applicable to site assembling large assembly welding of ordinary low carbon steel container, its purpose is to eliminate the residual stress and hydrogen.The vast majority of occasions is to choose a single high temperature tempering.Heat treatment of the heating and cooling shoulds not be too fast, and strive to inside and outside the wall even.
Heat treatment after welding can eliminate stainless steel relaxation of welding residual stress;Shape and size of stable structure, reducing distortion;To improve the plasticity of the weld metal,Improve the fatigue strength;Improve the ability of resistance to stress corrosion;To prevent the occurrence of delayed crack, and so on, so the stainless steel heat treatment after welding is very important.