Inconel 718合金δ相含量的测定及δ相析出

DETERMINATION OF δ PHASE FRACTION AND PRECIPITATION BEHAVIOUR OF δ PHASE IN INCONEL 718 ALLOY

采用X射线衍射技术测定了Inconel 718合金s相含量,研究了冷轧变形对δ相形貌、分布及数量的影响。结果表明,在ε=25%变形条件下,δ相首先在初始孪晶界及晶界上析出,随后在再结晶晶界上及晶内析出;在ε≥40%变形条件下,δ相首先在初始孪晶界、晶界及变形带上析出,并且随冷轧变形量增加,在变形带上的析出量增加。在910℃保温4 h条件下,随冷轧变形量增加,δ相析出形貌由针状逐渐变为颗粒状。冷轧变形促进了δ相析出。

The δ phase fraction in Inconel 718 alloy has been determined by X-ray diffraction techniques. The influence of reduction rate in cold rolling on morphology, distribution and fraction of δ phase has been studied. It has been found that δ phase first precipitates at the prior grain and twin boundaries, and then precipitates at the grain boundaries of the recrystallized grains and in the grains for the cold rolled alloy with 25% reduction rate, whereas for the cold rolled alloy with more than 40% reduction rate, δ phase first precipitates at the prior grain and twin boundaries and deformation hands, and the amount of δ phase at the deformation bands increases with increasing reduction rate in cold rolling. At the temperature of 910℃ for 4 h, the morphology of δ phase changes gradually from needles to spheroids with increasing reduction rate of cold roiling. Cold working promotes the precipitation of δ phase.