ABSTRACT

The effect of heat treatments on wire and arc additively manufactured Inconel 625 parts was investigated using in situ synchrotron X-ray diffraction and hardness testing. As-built samples revealed the presence of a γ-matrix with precipitation of γ′, γ′′ and MC carbides. When heat treated at 750°C for 4 h, γ′′ phase precipitated increasing the hardness by 5%. In situ X-ray observations revealed that heat treating at 870°C for 1 h resulted in δ-phase precipitation. Two different second-stage temperatures were tested (1050°C and 1150°C), which dissolved the δ-phase while MC carbides formed upon cooling. The second stage at 1150°C had a higher deleterious effect than the one performed at 1050°C due to extensive grain growth.

摘要

使用原位同步加速器 X 射线衍射和硬度测试研究了热处理对线材和电弧增材制造的 Inconel 625 零件的影响。竣工样品显示存在 γ 基体，并伴有 γ'、γ'' 和 MC 碳化物的沉淀。当在750℃热处理4h时，γ′′相析出，硬度提高5％。原位X射线观察表明，870℃热处理1小时导致δ相析出。测试了两种不同的第二阶段温度（1050°C 和 1150°C），在冷却时溶解 δ 相，同时形成 MC 碳化物。由于晶粒广泛生长，1150°C 下的第二阶段比 1050°C 下的第二阶段具有更高的有害影响。