Influence of deep cryogenic treatment on the microstructure and properties of AISI304 austenitic stainless steel A-TIG weld. (3rd April 2017)

• Record Type: Journal Article
• Authors: Cai, Y.; Luo, Z.; Zeng, Y.
• Is Part Of: Science and technology of welding & joining. Volume 22:Number 3(2017)
• Page Start: 236
• Page End: 243
• Publication Date: 2017-04-03
• Subjects: AISI304 austenitic stainless steel -- A-TIG weld -- Deep cryogenic treatment -- Intergranular corrosion resistance; Welding -- Periodicals; Joints (Engineering) -- Periodicals; Surfaces (Technology) -- Periodicals; 671.52
• DOI: 10.1080/13621718.2016.1222256
• Languages: English
• ISSNs: 1743-2936

Abstract

Abstract : Appropriate deep cryogenic treatment can improve comprehensive mechanical properties of the AISI304 austenitic stainless steel activating flux tungsten inert gas (A-TIG) welds. The microstructure of the welds before and after deep cryogenic treatment was all austenite with a small amount of δ-ferrite. The vermiform ferrite + austenite distributed in the whole weld, but the lath-shaped ferrite + austenite mixed components only distributed in the centre of the weld. The phases in the two welds were all Cr–Ni–Fe–C and Fe–Ni solid solutions, ferric carbide (i.e. Fe3 C) and chromic carbides (i.e. Cr23 C6 and Cr7 C3 ). After deep cryogenic treatment, the grain size of the weld was decreased a certain of degree, and the carbide phase content was increased. The strength and micro-hardness of the weld joints were increased due to the grain refinement. The intergranular corrosion resistance of the weld was reduced because the precipitation of chromium carbides at the austenite grain boundary.