Effect of the cooling rate on the microstructure and mechanical properties of high nitrogen stainles

• 作 者: Ming Zhu Wang Kehong Liu Zeng Wang Wei Wang Youqi
• 机 构: School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 2
• 出 处: 中国焊接
• 发表日期: 2020年2期
• 关键词: high nitrogen stainless steel welding cooling rate microstructure mechanical pro

The microstructure and mechanical properties of high nitrogen steel (HNS) weld metals prepared under air-and water-cooling conditions are investigated, and the effect of the cooling rate on these properties is discussed. The results indicate that an increase in the cool-ing rate could significantly increase the nitrogen content in HNS weld metals, especially for weld metals with a nitrogen content of 0.85％. Moreover, increasing the cooling rate could result in an increase in the tensile strength of HNS weld metals, which is found to be strongly de-pendent on the nitrogen content of the HNS sample. For high nitrogen austenitic stainless steel welding wire with lower nitrogen content, in-creasing the cooling rate could significantly improve its tensile strength, but a higher cooling rate has no influence on weld metals with nitro-gen content less than 0.58％. The tensile strength of the joint reached 850 MPa.