Microstructure evolution and mechanical properties of 316H weld metal during aging. Issue 7 (2nd May 2020)

• Record Type: Journal Article
• Authors: Wei, Shitong; Zhao, Langlang; Gao, Dianbao; Lu, Shanping
• Is Part Of: Materials science and technology. Volume 36:Issue 7(2020)
• Page Start: 793
• Page End: 804
• Publication Date: 2020-05-02
• Subjects: Tungsten inert gas welding -- aging treatment -- δ-ferrite -- M23C6 -- σ phase -- mechanical property; Materials science -- Periodicals; Microstructure -- Periodicals; Metallurgy -- Periodicals; 620.1105
• DOI: 10.1080/02670836.2020.1743597
• Languages: English
• ISSNs: 0267-0836

Abstract

ABSTRACT: A standard 316H welding wire was used to obtain 6% δ-ferrite in the weld metal by the automatic tungsten inert gas welding. The effect of aging time at 750°C on microstructure and mechanical properties of the weld metal were analysed. The results showed that as the aging time increased, the δ-ferrite fraction decreased, and finally, δ-ferrite was no longer seen, the M23 C6 fraction first increased and then decreased, and the σ phase fraction increased. Finally, the fractions of M23 C6 and σ phase kept stable, but the size increased. Accordingly, as the aging time increased, the yield and tensile strengths first decreased significantly, then increased obviously and finally decreased slightly again, while the elongation and impact energy decreased all the time.