新型高强度抗热腐蚀单晶高温合金研究

对新研发的M09A高强度抗热腐蚀单晶高温合金的组织结构、力学性能、抗热腐蚀性能及长期时效组织性能稳定性进行了研究。结果表明：M09A合金相对IN738合金适当降低Cr含量,为增加强化元素含量提供了可能,从而提高了M09A合金沉淀强化和固溶强化水平;取较低的Ti/Al比可以改善组织稳定性;应用单晶技术和高温热处理,可进一步提高M09A合金的高温力学性能、抗热腐蚀性能和组织性能稳定性;M09A合金抗热腐蚀性能与IN738合金的相当,高温力学性能超过现有的抗热腐蚀合金和典型的高强度定向凝固合金DZ125的,并达到第1代单晶合金的水平;合金组织性能稳定,不含Re、Ru、Hf等贵重金属元素,成本低,密度小,铸造性能较好。

Study of a High Strength and Hot-corrosion-resistant Single Crystal Superalloy

The microstructure,mechanical properties,hot-corrosion-resistance and stability of structure of a high strength and hot-corrosion-resistant single crystal superalloy M09A developed newly were studied.The results show that the decreasing in a little of Cr content compared to IN738 allows to further increase the strengthening elements content and enhance the precipitation and solution strengthening action for M09A.The stability of microstructure can be improved in lower Ti/Al ratio.The high-temperature mechanical properties,hot corrosion-resistance and stability of microstructure of the alloy are further improved by the single crystal technique and high-temperature heat treatment.The hot corrosion-resistance of M09A is equivalent to IN738,the high-temperature mechanical properties of M09A are higher than those of commercial hot corrosion-resistant alloys and high strength directionally solidification alloy DZ125,and reach the level of the first generation single crystal superalloys.The structure properties of the alloy are stable.In addition,it does not contain precious metal elements,such as Re,Ru and Hf,so it is cheaper and lighter.It has a good casting ability.