Baisukhan Adirek, Naksuk Nirut, Insua Pinmanee, Nakkiew Wasawat, Wisittipanit Nuttachat
Department of Industrial Engineering, Faculty of Engineering, Chiang Mai University, Chiang Mai 50200, Thailand.
National Metal and Materials Technology Center (MTEC), National Science and Technology Development Agency, Pathum Thani 12120, Thailand.
Materials (Basel). 2024 Jul 31;17(15):3768. doi: 10.3390/ma17153768.
This study investigates the effects of post-weld heat treatment (PWHT) on the microstructures and mechanical properties of plasma arc-welded 316 stainless steel. The experimental parameters included the solid solution temperatures of 650 °C and 1050 °C, solid solution durations of 1 h and 4 h, and quenching media of water and air. The mechanical properties were evaluated using Vickers hardness testing, tensile testing, scanning electron microscopy (SEM), and optical microscopy (OM). The highest ultimate tensile strength (UTS) of 693.93 MPa and Vickers hardness of 196.4 in the welded zone were achieved by heat-treating at 650 °C for one hour, quenching in water, and aging at 500 °C for 24 h. Heat-treating at 650 °C for one hour, followed by quenching in water and aging at 500 °C for 24 h results in larger dendritic δ grains and contains more σ phase compared to the other conditions, resulting in increased strength and hardness. Additionally, it shows wider and shallower dimple structures, which account for its reduced impact toughness.
本研究调查了焊后热处理（PWHT）对等离子弧焊316不锈钢微观结构和力学性能的影响。实验参数包括650℃和1050℃的固溶温度、1小时和4小时的固溶时间以及水和空气的淬火介质。使用维氏硬度测试、拉伸测试、扫描电子显微镜（SEM）和光学显微镜（OM）对力学性能进行评估。通过在650℃下热处理1小时、在水中淬火并在500℃下时效24小时，在焊接区获得了最高的抗拉强度（UTS）693.93MPa和维氏硬度196.4。与其他条件相比，在650℃下热处理1小时，然后在水中淬火并在500℃下时效24小时会产生更大的树枝状δ晶粒，并且含有更多的σ相，从而导致强度和硬度增加。此外，它显示出更宽且更浅的韧窝结构，这解释了其冲击韧性降低的原因。
