先进镍基单晶高温合金组织稳定性及力学行为的研究进展

发布时间：2018-04-28 14:11

本文选题：镍基单晶高温合金 + 组织稳定性　；参考：《金属学报》2015年10期

【摘要】：从先进镍基单晶高温合金的微观组织稳定性和力学行为2个方面,简要介绍了γ'相筏化、TCP相析出、高温和超高温低应力蠕变以及低周和热机械疲劳的主要研究进展.合金元素Ru的添加提高了合金的高温低应力蠕变寿命,但也间接促进了拓扑倒置现象的发生.随时效时间的延长和时效温度的升高,m相中的难熔元素含量都会明显增加;随着外加应力的增加,m相的析出量增加,压应力则相反.m相在析出的过程中会形成大量的面缺陷,这些缺陷会促进其它TCP相如P相和R相的形核.在高温低应力蠕变的过程中,镍基单晶高温合金中出现另一种重要的a010超位错,通过滑移和攀移相结合的方式在γ'相中缓慢运动.在超高温蠕变条件下,开始出现一个蠕变加速的孕育期,这与γ基体在超高温下不同程度的宽化有关.Ru的添加显著降低了合金的层错能,在低周疲劳的过程中可引起层错贯穿γ/γ'界面、a/6112Shockley拖后位错切入γ'相等复杂变形机制.在热机械疲劳的过程中,裂纹萌生的位置、微观结构的变化以及抗氧化性能都会影响镍基单晶高温合金的寿命.
[Abstract]:From two aspects of microstructure stability and mechanical behavior of advanced nickel base single crystal superalloy, the main research progress of 纬 'phase rafting TCP phase, high temperature and ultra high temperature low stress creep and low cycle and thermal mechanical fatigue are briefly introduced. The addition of Ru increases the creep life of the alloy at high temperature and low stress, but also indirectly promotes the occurrence of topologic inversion. With the increase of the applied stress, the compressive stress will form a large number of surface defects in the precipitation process, while the increase of the aging temperature and the increase of the aging temperature will obviously increase the content of refractory elements in the phase, and with the increase of the external stress, the compressive stress of the phase will form a large number of surface defects in the process of precipitation. These defects promote nucleation of other TCP phases such as P and R phases. During the creep process at high temperature and low stress, another important superdislocation a010 appears in the Ni-base single crystal superalloy, which moves slowly in 纬 'phase through the combination of sliding and climbing. Under the condition of ultra-high temperature creep, a creep accelerated incubation period began to appear, which is related to the addition of .Ru to the 纬 matrix at different degrees at ultra-high temperature, which significantly reduces the stacking fault energy of the alloy. During the low cycle fatigue process, the laminated faults can penetrate through the 纬 / 纬 'interface and a / 6112Shockley delayed dislocation cutting into the 纬' -equal complex deformation mechanism. During thermal mechanical fatigue, the location of crack initiation, the change of microstructure and oxidation resistance will affect the life of Ni-base single crystal superalloy.
【作者单位】：中国科学院金属研究所;
【基金】：国家高技术研究发展计划项目2014AA041701 国家自然科学基金项目51331005和11332010资助~~
【分类号】：TG132.3

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