电弧熔炼态NiAl-39V共晶合金的组织及力学性能

Microstructure and performance of NiAl-39V Eutectic Alloy prepared by Arc melting

摘要:

本文采用真空非自耗电弧熔炼制备了Ni-30.5Al-39V(at%)合金,利用光学显微镜(OM),X射线衍射(XRD),扫描电镜(SEM)分析了合金不同凝固位置处的相组成和组织形态,结果表明Ni-30.5Al-39V(at%)的凝固组织由NiAl+V片层共晶组成。通过断裂韧性和高温压缩的测试,结果表明NiAl-39V合金的断裂韧性是NiAl合金的三倍,裂纹偏转和裂纹键合是其主要韧化机理。高温强度提升约2倍左右,复相强化和固溶强化是高温强度提升的主要原因。最后,基于Arrhenius模型构建NiAl-39V合金本构关系为ε = 5.398×[sinh(0.037128σ)]_2.3exp(－109.95×10₃/RT),其激活能为109.95 kJ?mol_-1。

Abstract:

SNi-30.5Al-39V (at%) alloy is prepared by vacuum non-consumable arc meltingSin this paper.The phase composition and morphology of the alloy at different solidification positions were analyzed by optical microscopy (OM), X-ray diffraction (XRD) and scanning electron microscopy (SEM).And the results show that the solidification structure of Ni-30.5Al-39V(at%) is composed of NiAl+V sheet eutectic.Through the test of fracture toughness and high temperature compression, the results show that the fracture toughness of NiAl-39V alloy is three times that of NiAl alloy, and crack deflection and crack bonding are the main toughening mechanisms.Finally, based on the Arrhenius model, the constitutive relation of NiAl-39V alloy was constructed as ε = 5.398×[sinh(0.037128σ)]_2.3exp(-109.95×10₃/RT) and the activation energy was 109.95 kJ?mol_-1. Keywords: Eutectics; Room temperature fracture toughness; High temperature strength; Constitutive equation