2008 Volume 49 Issue 12 Pages 2844-2849
The feasibility and microstructural development of high-nitrogen-containing nickel-free austenitic stainless steel by small-scale resistance spot welding were studied. Almost fully austenitic cellular microstructure was developed in weld nuggets because the cooling rate of approximately 105 Ks−1 was much faster than that in conventional fusion welding processes. Only a small amount of delta ferrite was formed at the gamma grain boundary in the weld, and chromium nitride precipitation was observed both in the gamma grains and at the grain boundary. No significant defects and sensitization were observed in the weld nugget and in the heat affected zone, respectively, and an adequate joint strength was obtained.
