- By:
- Yamamoto, Yukinori ; Miller, Roger G; Seibert, Tim ; Bhattacharya, Arunodaya; Burke, Grace
- Page Number:
- 1249-1256
- Book Title:
- Advances in Materials, Manufacturing, and Repair for Power Plants: Proceedings from the Tenth International Conference
- Publication Date:
- March 12, 2026
- Publisher Location:
- ASM International, Ohio, United States of America
- Conference Name:
- 10th International Conference on Advances in Materials, Manufacturing & Repair for Power Plants
- Conference Location:
- Bonita Springs, Florida, United States of America
- Conference Sponsor:
- ASM International, EPRI
- View DOI Listing:
- https://doi.org/10.31399/asm.cp.am-epri-2024p1249
Abstract
A compositional modification has been proposed to validate an alloy design which potentially eliminates the requirement of post-weld heat treatment (PWHT) while preserving the advantage of mechanical properties in a reduced activation bainitic ferritic steel based on Fe-3Cr-3W-0.2V- 0.1Ta-Mn-Si-C, in weight percent, developed at Oak Ridge National Laboratory in 2007. The alloy design includes reducing the hardness in the as-welded condition for improving toughness, while increasing the hardenability for preserving the high-temperature mechanical performance such as creep-rupture resistance in the original steel. To achieve such a design, a composition range with a reduced C content combining with an increased Mn content has been proposed and investigated. Newly proposed “modified” steel successfully achieved an improved impact toughness in the as- welded condition, while the creep-rupture performance across the weldments without PWHT demonstrated ~50% improvement of the creep strength compared to that of the original steel weldment after PWHT. The obtained results strongly support the validity of the proposed alloy design.
