IC-218合金的再结晶织构及其形成机制

RECRYSTALLIZATION TEXTURE OF IC-218 ALLOY

研究了IC 2 1 8合金冷轧 60 %后在 1 0 0 0°C退火中形成的织构 ,发现再结晶后晶粒取向分布漫散 ,这种情况早在再结晶形核阶段就已出现 ,并在随后的长时间退火中保持。相继出现几个弱的再结晶织构 ,它们都与冷轧织构之间存在与低Σ重合点阵相近的位向关系。这些结果可与显微组织的观察很好地相互印证 ,表明导致再结晶织构这些特点的基本原因是一般大角晶界失去明显可动性而以位错运动为机制的界面迁移则相对活跃。将以上结果与单相Ni3Al的再结晶行为进行对比 ,发现两者极为相似。由此对 76Ni 2 4Al 0 2 4B合金的晶界结构是否存在无序区的问题提供了新的信息。

The recrystallization texture of IC-218 alloy developed during 1000℃ annealing after 60% cold rolling was investigated. The orientation distribution of new grains was found almost random, which took shape at the early stage of the annealing and kept basically unchangeable during subsequent long time annealing. Three weak texture components gradually developed in succession, which were all found to be related to the cold rolling texture by low Σ orientation relationship. The study was well consistent with the microstructure observation, which indicated the recrystallization texture resulted from the fact that random high-angle boundaries lost mobility while boundary migration based on dislocation movement was relatively active. It was interesting to note that the above results were quite similar to the recrystallization behavior of single-phase Ni 3Al, which threw some light on the long-standing controversy over whether a disorder zone (γ layer) existed at grain boundaries in 76Ni-24Al-0.24B alloy.