论文部分内容阅读
研究了降Nb提Al对GH706合金组织和力学性能的影响。当合金中Al含量由0.35%提高至1.26%(质量分数,下同),Nb含量由2.88%降低至1.98%后,可抑制晶内主要强化相γ″-Ni3Nb相的析出,促进γ′-Ni3Al相的析出,显著降低合金的室温屈服强度,但明显改善了合金的室温冲击性能。同时提Al降Nb还抑制了晶界强化相η-Ni3(Ti,Nb)相的析出,使得富Nb的Laves相及富Nb、Cr的Cr2Nb相析出,弱化了高温下的晶界强度,极大地恶化了合金的持久性能。
The effect of reducing Nb on the microstructure and mechanical properties of GH706 alloy was studied. When the content of Al in the alloy is increased from 0.35% to 1.26% (mass fraction), the content of Nb decreases from 2.88% to 1.98%, the precipitation of γ "-Ni3Nb phase in the grain can be suppressed and the γ’- The precipitation of Ni3Al phase significantly reduces the room temperature yield strength of the alloy, but significantly improves the room temperature impact properties of the alloy.Also, the addition of Al decreases the precipitation of η-Ni3 (Ti, Nb) Laves phase and Nb, Cr rich Cr2Nb phase precipitation, weakening the grain boundary strength at high temperatures, which greatly deteriorates the durability of the alloy.