Toughening of AISI 410 Stainless Steel Through Quenching and Partitioning and Effect of Prolonged Aging on Microstructur
- PDF / 2,319,661 Bytes
- 7 Pages / 593.972 x 792 pts Page_size
- 25 Downloads / 165 Views
ISI 410 stainless steel (SS) is used widely in hydropower plants, nuclear power plants and different machine parts because of its high strength, good tribological properties and low cost. This steel undergoes segregation-induced temper embrittlement while tempering in the temperature range of 723 K to 923 K following normalizing.[1–4] This reduces the cohesive
KIRTIRATAN GODBOLE and BHARAT B. PANIGRAHI are with the Department of Materials Science and Metallurgical Engineering, Indian Institute of Technology Hyderabad, Kandi, Sangareddy, 502285, India. Contact e-mail: [email protected] C.R. DAS is with the Indira Gandhi Centre for Atomic Research, Kalpakkam, 603102, India and also with the Homi Bhabha National Institute, Kalpakkam, 603102, India. Contact e-mail: [email protected] J. JOARDAR is with the International Advanced Research Centre for Powder Metallurgy and New Materials (ARCI), PO Balapur, Hyderabad, 500005, India. S.K. ALBERT is with the Indira Gandhi Centre for Atomic Research. M. RAMJI is with the Mechanical & Aerospace Engineering, Indian Institute of Technology Hyderabad, Kandi, Sangareddy, 502285, India. Manuscript submitted October 29, 2019.
METALLURGICAL AND MATERIALS TRANSACTIONS A
strength of boundaries, resulting in reduced toughness after tempering. Gopa et al.[1] reported a significant reduction in toughness of 12Cr steel with increasing tempering temperature from 473 K to 823 K. This reduction was attributed to the presence of needleshaped precipitates at the prior austenite grain boundaries (PAGBs).[1,5] For this reason, this steel was never used or heat treated between 723 K and 923 K. However, for industrial requirements, nitriding is essential to improve its surface properties. Unfortunately, this heat treatment temperature falls within the aforementioned tempering temperature range where the toughness of steel deteriorates significantly to an unexpected level. To improve the strength and ductility of low-alloy, bainitic and high-alloy steels, researchers have previously used quenching and partitioning (Q&P) heat treatments.[6–10] Recently, Godbole et al. proposed Q&P to overcome temper embrittlement in 12Cr steel using a grain boundary engineering approach.[11] Improved toughness was reported after 1 hour tempering at 823 K compared with tempering after normalizing, which was attributed to the increased fraction of coincidence site lattice boundaries.[11] As this steel requires longer nitriding durations, similar to aging, to achieve the required nitride layer on the surface, one needs to understand its long-term effect on the microstructure and mechanical properties of this steel. The objective of the present investigation is to improve the toughness of AISI 410 SS at a temperature where the material attains minimum toughness during prolonged tempering so that this steel can be used in industries. AISI 410 SS containing C: 0.14, Cr: 12.12, Si: 0.41, Mn: 0.97, S: 0.01, P: 0.01, As: 0.001, Sb: 0.001, Sn: 0.03 and balance Fe (in wt pct) was used in the present study. Three different sets of
Data Loading...
