铁镍钴基高温合金雾化粉末烧结特性及显微组织

Sintering Properties and Microstructure of Fe-Ni-Co-based Superalloy Atomized Alloy Powder

摘要:

采用雾化法制备了Fe18Ni23Co25Cr21Mo8WNb3C2高温合金粉末，并对其物相、显微形貌和热稳定性进行了表征。在此基础上，将雾化粉末进行真空热压烧结和二次烧结，获得了奥氏体为基体、M6C碳化物作为主要强化相的铁镍钴基高温合金。结果表明，真空热压烧结后，组织分布较均匀，抗拉强度较高，但是延伸率较低。对热压烧结块材进行二次烧结，有利于合金块材的基体和强化相组织分布更加均匀，在抗拉强度略有降低基础上较大幅度提高烧结块材延伸率。

Abstract:

Fe18Ni23Co25Cr21Mo8WNb3C2 superalloy powders were synthesized via atomization method, and phase composition, morphology and thermal stability of composite powders were respectively characterized. Based on the above analysis, atomized alloy powders were fabricated by vacuum hot-pressed sintering and further second sintering. The sintering Fe-Ni-Co-based superalloy mainly consists of austenite phase and M6C carbide phase, which was a strengthening phase. Experiment results indicate that superalloy have uniform structure, high tensile strength and low elongation after vacuum hot-pressed sintering. Further second sintering, microstructure of superalloy become more homogeneous, the tensile strength decreases slightly and the elongation rate significantly increases.