K438铸造镍基高温合金的显微组织与力学性能研究

Research on Microstructure and Mechanical Properties of K438 Casting Nickel Base Superalloy

采用金相显微镜、扫描电镜研究了试验K438合金的显微组织及其断口形貌,并分析了K438试验合金室温塑性低的原因。结果表明:K438合金经热处理后,析出相主要由颗粒状、块状和长条状的MC型碳化物构成。K438合金中存在长条状MC型碳化物是导致室温伸长率降低的主要原因。

The microstructure and fracture morphology of K438 alloy were studied by metallographic microscope and scanning electron microscope,and the reasons for the low room temperature plasticity were analyzed.The results show that the precipitated phase of K438 alloy is mainly composed of granular,massive and long strip MC carbides.The presence of long strip MC carbide in K438 alloy is the main reason for the decrease of elongation at room temperature.