不同热处理工艺对GH4169合金组织及性能的影响

Effect of Different Heat Treatments on Microstructures and Properties of GH4169 Alloy

研究了3种不同热处理工艺对GH4169合金组织和性能的影响。结果表明,3种热处理对晶粒大小没有明显影响,而主要改变δ相的析出量以及分布。通过HST处理后在晶界以及晶内可获得较多的δ相;通过DA处理的组织晶界处较平滑,几乎没有δ相析出;而通过ST处理的δ相主要析出于晶界,数量介于两者之间。在650℃,725MPa的蠕变条件下,通过DA处理可获得更长的蠕变寿命和断裂延伸率,而ST处理后的合金寿命最短。对合金蠕变后的试样观察发现:δ相的数量、分布对合金蠕变性能有着重要的影响。

The effects of three heat treatments on microstruetures and properties of GH4169 alloy were investigated. It is found that the three heat treatments almost have no effect on the grain sizes but change the precipitation and distribution of δ phases. The alloy materials treated by HST have more δ phases both at grain boundaries and crystal interior; after DA treatment, the grain boundaries are smooth, and δ phases could hardly be found; δ phases mainly precipitated at the grain boundaries by ST treatment, and the quantity of δ phases is between that after HST and DA treatment. Under 650 ℃, 725 MPa creep condition, there are longer life and elongation to failure by DA treatment while the alloy materials have the lowest life after ST treatment. It is concluded based on the results that the quantity and distribution of phases have great effects on creep properties.