Effect of Post-Weld Heat Treatment on the Mechanical Properties and Microstructure of P-No. 1 Carbon Steels

Abstract

This study aims to investigate the suitability of requirement for post-weld heat treatment(PWHT) temperature when different P-No. materials are welded, which is defined by ASME Sec. III Code. For SA-516 Gr. 60 and SA-106 Gr. B carbon steels that are typical P-No. 1 material, simulated heat treatment were conducted for 8 h at 610℃, 650℃, 690℃, and 730℃, last two temperature falls in the temperature of PWHT for P-No. 5A low-alloy steels. Tensile and Charpy impact tests were performed for the heat-treated specimens, and then microstructure was analyzed by optical microscopy and scanning electron microscopy with energy-dispersive spectrometry. The Charpy impact properties deteriorated significantly mainly due to a large amount of cementite precipitation when the temperature of simulated heat treatment was 730℃. Therefore, when dissimilar metal welding is carried out for P-No. 1 carbon steel and different P-No. low alloy steel, the PWHT temperature should be carefully selected to avoid significant deterioration of impact properties for P-No. 1 carbon steel.

Effect of Post-Weld Heat Treatment Temperature on the Mechanical Properties and Microstructure of Weld Heat-Affected Zone of Low-Alloy Steel for Nuclear Reactor Pressure Vessel

“…PWHT는 선행연구와 동일한 방법으로 ASME 기술 기준에 따라 수행하였다 11,15) . 모재 및 재현 HAZ 시편 을 열처리로에 장입한 후 610℃, 650℃, 690℃, 730℃…”

Effect of heat treatment on microstructure and mechanical properties of AG728 steel joints welded with ER90S-G wires

“…This characteristic leads to the generation of significant residual stresses after welding, while the operating environment is notably harsh, potentially causing issues such as stress corrosion cracking [4,5]. Post-weld heat treatment serves as an effective method to enhance joint performance; however, treatments involving high temperatures and extended durations may diminish the properties of welded joints [6][7][8].…”

Solidification behaviour and microstructure of welding transition zone using low-transformation-temperature welding consumables

“…This undesirable and harmful stress makes the weld joints more susceptible to fatigue failure [1]. There are several ways to reduce the harmful tensile residual stresses and improve the fatigue strength, such as post-weld heat treatment [2] and shot peening [3, 4]. However, in practice, these two ways are always associated with high cost.…”