摘要
研究了固溶处理温度对GH4169G合金晶粒组织、晶界析出和蠕变的影响。结果表明,随着固溶处理温度的提高(由980℃提高到1020℃)GH4169G合金的晶粒尺寸明显增大,晶界d相的尺寸和数量明显减少,晶内g″相的析出变化不大;合金的650℃/700 MPa稳态蠕变速率明显降低,表观蠕变激活能明显增大,蠕变断裂寿命显著延长。固溶处理温度对680℃/725 MPa的蠕变性能有相同的影响趋势,但其程度减弱。孪晶的形成是GH4169G合金的重要蠕变机制。提高固溶处理温度使晶界d相的析出减少,晶界滑动蠕变速率降低;同时使晶粒度增大,形成孪晶的阻力增大,晶粒蠕变速率降低。
Effects of solution temperature on grain structure, grain boundary precipitation and creep behavior of GH4169G alloy have been investigated, and the creep mechanism and the reason for solu- tion temperature influencing the creep of the alloy has been discussed. When the solution temperature is increased from 980℃ to 1020℃ the 3 phase precipitation at the grain boundaries markedly decreased, and the grain size largely increased, but the r″ precipitation within the grain matrix is not influenced no ticeably. In addition, the steady state creep rate at 650℃/700 MPa is greatly lowered, and the apparent activation energy is largely increased, and the creep rupture life is noticeably extended. It was deter- mined through TEM observation that GH4169G alloy creeps mainly by twinning. The decreasing ＆ phase precipitation helps to inhibit the creep through grain boundary slip, and the enlarged grain size naturally prohibits the twinning and hence mitigates the creep through grain deformation. As a result, the steady state creep rate of GH4169G alloy is decreased and the creep rupture life is extended.
出处
《材料研究学报》
EI
CAS
CSCD
北大核心
2013年第4期444-448,共5页
Chinese Journal of Materials Research
