低磷GH169和常规GH169合金力学性能的对比研究

Study on Mechanical Properties of Low Phosphorous and Conventional GH169 Deformation Alloys

对国内生产的低磷GH169[s（P）＜0．001％]及常规GH169[w（P）0.008％～0．013％]变形合金锻件的力学性能进行了对比研究。结果表明，室温拉伸和高温拉伸强度未显现很大差异，然而低磷GH169合金反而显示出高温塑性特别是650℃／686MPa持久塑性的明显降低，且低磷合金在蠕变和疲劳／蠕变交互作用下的裂纹扩展速率皆高于常规合金，低磷合金的595℃／895MPa缺口周期持久寿命亦有降低的趋势。俄歇能谱分析表明，磷在晶界发生偏聚，透射电镜观察，发现低磷合金中的σ相的片状形式沿晶界析出，而磷含量提高使σ相的胞状形式沿晶界析出。

The comparison in mechanical behavious between low phosphorous INCONEL718[P<0.001 %(w/%)] and conventional INCONEL718[P0.008%~0.013%(w/%)] deformation alloys shows that there is no obvious difference in tensile strength between the low P content and conventional INCONEL718 alloys at room temperature and elevated temperature. However, the ductilities of the low content alloy obvioushy decrease at 650℃ /686MPa. And the crack propagation rates of the low P content alloy under 650℃ creep, futige and creep/fatigue interaction conditions are higher than that of the conventional alloy, and it seems that there is a tendency that the cyclic notch stress rupture life of low P alloy decreases at 595℃/895MPa.