微量元素P、B对GH4169合金组织与蠕变性能的影响

通过对等温锻造合金进行直接时效、蠕变性能测试和组织形貌观察,研究了微量元素P、B对GH4169合金组织结构及蠕变行为的影响.结果表明:添加微量P、B可促使粒状δ相在合金中析出,且沿晶界不连续析出的δ相可抑制晶界滑移,提高合金的蠕变抗力;在试验温度和应力范围内,测定出GH4169G合金具有较高的蠕变激活能Q=594.7 ...

Influence of trace phosphorus and boron on microstructure and creep behavior of GH4169 superalloy

By means of direct aging treatment,creep properties measurement and microstructure observation of the ITF alloys,the influence of trace P and B on microstructure and creep behaviors of GH4169 alloy is investigated.Results show that,trace elements(P and B) can promote moreδ phase precipitating in the alloy,and theδ phase distributed along boundaries can restrain the boundaries slipping to enhance the creep resistance of the alloy.In the range of applied stresses and temperatures,the creep activation energy of the GH4169G alloy is measured to be Q=594.7 kJ/mol.During creep,the deformed mechanism of the GH4169 alloy is twinning deformation.However,the deformed features of the GH4169G alloy are twinning and dislocation slipping with double orientation in the grain,here,the δ particles can hinder the dislocation movement in the alloy.In the later creep stage,dislocations are congregated in the boundary regions to bring out the stress concentration and promote the cracks initiating and propagating along the boundaries,which is thought to be the fracture mechanism of the alloy during creep.