Promoting the dissolution of delta ferrites by cyclic heat treatment in martensitic heat-resistant steel. (March 2023)

• Record Type: Journal Article
• Authors: Zhang, Xu; Li, Junru; Zhang, Pengfei; Li, Yanhui; Li, Qi
• Is Part Of: Materials today communications. Volume 34(2023)
• Publication Date: 2023-03
• Subjects: Martensitic heat-resistant steel -- Delta ferrites -- Cyclic heat treatment -- Dissolution rate; Materials science -- Periodicals; 620.11
• DOI: 10.1016/j.mtcomm.2022.105006
• Languages: English
• ISSNs: 2352-4928

Abstract

Abstract: Quickly eliminating delta ferrites in martensitic heat-resistant stainless steel is a recurring problem. We found that cyclic heat treatment can significantly promote the dissolution of delta ferrites in martensitic heat-resistant stainless steel. Therefore, in this paper, the promoting mechanism of cyclic heat treatment on the dissolution of delta ferrites was examined. The results showed that shape and distribution position have important effects on the dissolution rate of delta ferrites. Under a single heating process, delta ferrites transferred from the boundaries to the interior of austenite grains, with the specific surface area significantly decreasing with heating time, which led to a decrease in the dissolution rate of delta ferrites. Cyclic heat treatment can keep the delta ferrites on the boundaries of austenite grains while maintaining a large specific surface area, which is the reason for the high dissolution rate of delta ferrites under the cyclic heat treatment process. Graphical Abstract: ga1