TP347H与Super304H耐热钢热疲劳过程的变形与开裂行为研究

Study on Deformation and Cracking Behavior of TP347H and Super304H Heat Resistant Steel during Thermal Fatigue

基于金属板材热疲劳试验方法(HB 6660-2011),对比分析了TP347H和Super304H两种耐热钢的供货态、相同热处理条件下的固溶态和时效态试样在热疲劳过程中底部尺寸的变形行为,以及缺口部位裂纹形貌。结果表明:这3种状态Super304H钢在热疲劳试验后的变形均小于相应TP347H钢的,TP347H缺口呈现相对较大的钝化,时效态试样钝化最大,裂纹最短。缺口附近的观察结果,TP347H在缺口附近龟裂损伤程度弱于Super304H钢的,开裂方式主要为沿晶开裂,也有部分穿晶开裂。

Based on the test method for thermal fatigue of metals with rectangular plate specimen(HB 6660-2011),the deformation behavior of the bottom dimension and the crack morphologies in the V mouth of TP347H and Super304H heat resistant steels in the as-supplied state,the solid solution state under the same heat treatment condition of the as-supplied state and the aging state samples during the thermal fatigue process were compared and analyzed.The results show that the deformations of Super304H steel in three states are less than that of TP347H steel after thermal fatigue test,the V mouth of TP347H shows relatively large passivation,and the aging sample has the largest passivation and the shortest crack.The observation of the V mouth shows that the damage degree of Super304H steel is weaker than that of TP347H steel.The cracking mode is mainly along the crystal cracking,but also part of the transgranular cracking.