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C1023是一种作导向器材料的镍基铸造合金。研究表明,该合金中有铸态σ相析出,铸态σ相是指在合金精铸凝固后未经任何热处理而析出的相。铸态σ相的分子式为CrMoNi_(0.73)Co_(0.47’)析出于枝晶间隙区内一次碳化物MC之周围,这是由于枝晶间隙区偏聚着Mo、Cr等元素,且一次碳化物MC是铸态σ相的生核场所。本文指出了铸态σ相的析出使合金的韧性、塑性、持久寿命和热疲劳性能显著下降,其原因是它和一次碳化物MC在合金中构成了一条脆性通道,使裂纹能迅速扩展。
C1023 is a nickel-based casting alloy for guide material. Studies have shown that there is precipitation of the σ phase in the alloy, and the as-cast σ phase refers to the phase precipitated without any heat treatment after the alloy is cast and solidified. The as-cast σ phase has the formula CrMoNi_ (0.73) Co_ (0.47 ’) precipitated around the primary carbides MC in the dendrite interstitial region due to the segregation of Mo, Cr and other elements in the dendrite interstitial region, and the primary carbides MC is a nucleation site of as-cast σ phase. This paper points out that the as-cast σ phase precipitates a significant decrease in the toughness, ductility, long-life and thermal fatigue properties of the alloy due to its brittleness in the alloy with the primary carbides MC and the rapid propagation of cracks.