不锈钢堆焊层剥离断裂的金属学本质

Metallographic Essence of Hydrogen-induced Disbonding of Stainless Weld Overlay

摘要: 通过电解充氢试验研究了不锈钢堆焊层剥离断裂的影响因素,并着重分析了这一断裂问题的金属学本质。结果显示,经过焊后热处理,堆焊过渡区碳、铬元素均有迁移。在氢致剥离裂纹产生的区域,碳和合金元素分布有突变。研究也表明,碳化物沉淀、相变产物的存在及其与空位、位错等微观缺陷、应力、进入金属内部的氧的交互作用,是剥离断裂产生和发展的主要原因。

Abstract: The factors influencing hydrogen-induced disbonding were studied through a series of electrolytic hydrogen charging tests.The essence of metallography concerning the cracking was analyzed thoroughly.The results showed that there is a migration of carbon and chromium after PWHT.There are abrupt changes in the distribution of carbon and alloy elements in the region of initiation of hydrogen-induced disbonding.The studies showed that the initiation and growth of cracks might be caused primarily by the deposited carbide and transformation production as well as the action between these and dislocations, stress and hydrogen in the material.