一种性能优异的低成本定向凝固镍基高温合金DZ417G

A DIRECTIONALLY SOLIDIFIED NICKEL-BASE SUPERALLOY DZ417G WITH EXCELLENT PROPERTIES AND LOW COST

一种新的定向凝固镍基高温合金DZ417G已被研制成功,它不含有稀缺昂贵的金属元素W,Nb,Ta,Hf等元素,具有密度小、成本低的特点.简要地介绍这一合金的研究结果,包括化学成分的确定,定向凝固工艺和热处理制度的选定,所测试的各种力学性能;涉及不同温度的瞬时拉伸性能,冲击韧性,持久、蠕变性能及其机理,高、低周疲劳和冷热疲劳性能,疲劳裂纹扩展速率,长期时效后组织和力学性能的变化以及抗氧化性能和物理性能.结果表明,DZ417G合金是一种综合性能优异的定向凝固镍基高温合金,很多性能指标优于DZ4合金,与DZ22和DS CM247LC合金相当。可用作先进航空发动机低压涡轮叶片等零件.

A new directionally solidified Ni-base superalloy DZ417G without rare and expensive elemental additions, such as W, Nb, Ta, and Hf, had been successfully developed for the low density and cost. In this paper, the study results on superalloy DZ417G, including the selection of chemical composition, the DS processing and the heat treatment have been introduced briefly. Then the mechanical properties, such as the tensile properties at various temperatures, the impact toughness, the stress-rupture life, the creep behaviors and possible mechanisms, LCF, HCF and thermal fatigue behaviors, the growth behaviors of fatigue cracks, the microstructure and mechanical properties after long aging, the oxidation resistant property and physical property, have been also investigated. It is concluded that the comprehensive properties of DZ417G alloy are almost the same as those of DZ22 and DS CM247 LC, and better than those of DZ4 alloy. Therefore, it is thought that DZ417G alloy can be used for the blades in advanced air engine.