电子束表面熔凝处理对镍基高温合金熔凝层组织及其抗高温氧化性能的影响

Effect of Electron Beam Surface Solidification on Microstructure and High Temperature Oxidation Resistance of Ni-base Alloy Solidified Layer

采用电子束表面熔凝处理方法研究了电子束表面熔凝处理M38G高温合金熔凝层组织和熔凝层组织对高温氧化的影响。结果表明 :试样经电子束表面熔凝处理后 ,根据扫描电镜观察可见 ,在扫描速率不变的情况下 ,随着电子束作用能量的降低 ,其熔凝层组织明显细化 ,在试验条件下可达 2 μm左右。采用箱式电阻炉进行 10 0 0℃× 10 0h空气静态氧化试验 ,结果表明 :试样在 10 0 0℃氧化 10 0h后 ,所形成的氧化膜组织仍然比较细小 ,EDS分析结果显示氧化膜以氧化铬为主 ,氧化过程中形成的氧化膜未破裂 ,起到了对基体的保护作用。

The effect of electron beam surface solidification treatment on microstructure of superalloy M38G and oxidation resistance of solidified layer has been studied. The result shows that if scanning speed is constant, with the decrease of electron beam energy the microstructure becomes finer obviously under SEM and reaches around 2μm. Samples are isothermally oxidized at 1000°C for 100 hrs. The result shows that the oxide scale structure is still finer after oxidation, and chromium oxide scale is formed, during oxidation the scale is not peeled off, therefore can protect the substrate.