一种抗热腐蚀定向高温合金热处理组织及性能研究

The Research of the Heat-treated Microstructure and Properties of a Hot Corrosion Resistant Directionally Solidified Superalloy

研究了抗热腐蚀定向凝固高温合金DZ483的热处理组织和性能。结果表明:合金热处理后,硼化物和η相消失,γ'相的尺寸更加均匀,形貌更加规则,MC碳化物发生轻微分解,析出颗粒状M6C碳化物;标准热处理试样的拉伸强度从室温到650℃左右是逐渐上升的,从650℃左右到900℃以上则是明显下降的;在标准热处理基础上,提高固溶温度,合金强度有所提高,塑性变化不大;延长时效时间,合金的拉伸塑性提升,强度变化不大;提高固溶温度可以显著改善合金的持久寿命,持久延伸率也略有提升;延长高温时效时间可以改善合金的持久塑性,持久寿命也有所增加。

The heat-treated microstructure and mechanical properties of a hot corrosion resistant directionally solidified superalloy DZ483 were investigated.The results show that after heat treatment,the boride andηphases disappear,the size of theγ'phase is more uniform and the morphology is more regular,MC carbides are slightly decomposed and granular M6C carbides are precipitated;The tensile strength increases as temperature rises from room temperature to 650°C,and decreases significantly as temperature rises from about 650°C to more than 900°C.On the basis of standard heat treatment,the strength of the alloy is increased with improving the solution temperature;the tensile plasticity is improved with increasing the aging time.Increasing the solution temperature can significantly improve the stress rupture life of the alloy,and the elongation is also slightly improved;extending the high-temperature aging time can improve the plasticity of the alloy,and the rupture life is also increased.