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通过对热等静压态FGH95合金进行完全热处理、组织形貌观察、点阵常数测定和蠕变曲线测定,研究了FGH95镍基合金的组织结构和蠕变机制。结果表明:合金经热等静压成型后,粗大相沿原始颗粒边界不连续分布,经高温固溶和时效处理后,晶粒尺寸无明显变化,粗大相数量减少,且细小相和MC碳化物在合金中弥散析出,可提高合金蠕变抗力,同时由于相形成元素Al、Ti溶入基体,经XRD谱线测定,相的平均点阵常数减小,而基体相平均点阵常数增加,致使/两相晶格错配度减小;在实验温度和应力范围内,测得合金的蠕变激活能为630.4kJ/mol。在蠕变期间,FGH95合金的蠕变机制是位错在基体中运动或剪切相,其中,蠕变位错以Orowan机制绕过相,而<110>超位错切过相发生分解形成(1/3)<112>超肖可莱不全位错+层错的位错组态。
The structure and creep mechanism of FGH95 nickel-base alloy were investigated by means of complete heat treatment, microstructure observation, lattice constant determination and creep curve determination. The results show that the coarse grains are discontinuous along the boundaries of the original grains after hot isostatic pressing. The grain size does not change obviously and the number of coarse grains decreases after solution treatment and aging treatment at high temperature. The dispersion of alloy can increase the creep resistance of the alloy. At the same time, as the phase forming elements Al and Ti dissolve into the matrix, the average lattice constant of the phase decreases and the average lattice constant of the matrix increases due to the XRD spectrum, The lattice mismatch between the two phases decreases. The creep activation energy of the alloy is 630.4kJ / mol within the experimental temperature and stress range. During creep, the creep mechanism of the FGH95 alloy is that the dislocations move or shear in the matrix, in which creep dislocations bypass the phase with the Orowan mechanism and the <110> super-dislocated phase breaks down to form ( 1/3) <112> Chaos Klein Dislocation + stacking fault dislocation configuration.