热处理工艺对GH4169G合金组织与性能的影响

Influence of Heat Treatment Technologies on Microstructure and Creep Properties of GH4169G Alloy

摘要: 通过对等温锻造GH4169G进行不同工艺的热处理和组织形貌观察，研究了热处理工艺对合金组织与蠕变性能的影响。结果表明，GH4169G合金经直接时效处理后的组织结构由γ基体、γ^'、γ^''及δ相组成，且晶粒尺寸约为10 μm~15 μm，并存在较多孪晶组织，其中，粒状δ相分布于晶内，而大量细小γ^'和γ^''强化相在晶内弥散析出，是使合金具有较好蠕变性能的主要原因。与直接时效处理合金相比，经标准热处理后，合金的晶粒尺寸无明显变化，组织结构仍由γ基体、γ^'、γ^''及δ相组成，但孪晶数量明显减少，且有块状和针状δ相沿晶界不连续析出，其中，元素Fe、Cr富集于近晶界区域，是使其δ相具有针状形态的主要原因。

Abstract: By means of heat treatment and microstructure observation, an investigation has been made into the influence of the heat treatement technologies on the microstructure of GH4169 alloy. Results show that, after the isothomal forged alloy is directly aged treated, microstructure of the alloy consists of the γ matrix,γ^' and γ^''phases, the size of the grains is about 10 - 15 μm, thereinto, significant amount of the particle-like δ precipitates are distributed within the grains, which is thought to be the main reason of the alloy possessing a better creep properties. Compared to the direct aged alloy, after standard heat treated, no change in the grains size and phases constituted is detected in the alloy, but the quantity of the twinning decreases, and some block-like and signficant amount of needle-like δ phase are precipitated along the boundaries, which is attributed to the effect of the elements Fe and Cr distributed in the boundaries region.