罗超,商玉洁,高振桓,王西涛,何金珊

• 1:清洁高效透平动力装备全国重点实验室
• 2:东方电气集团东方汽轮机有限公司
• 3:北京科技大学钢铁共性技术协同创新中心
• 4:齐鲁工业大学(山东省科学院)

摘要(Abstract)：

研究了等轴Mar-M247高温合金在800℃热暴露长达24000 h过程中的组织演变规律和800℃的高温拉伸强度和塑性。结果表明：热暴露5000 h前，合金的枝晶干二次γ′相、三次γ′相尺寸显著增大，热暴露5000～240000 h时，枝晶干二次γ′相尺寸没有明显变化，枝晶干三次γ′相尺寸略微增长。随热暴露时间延长，枝晶干二次γ′相体积分数增大，三次γ′相体积分数下降。根据两种γ′相的尺寸分布(PSD),两种γ′相的粗化均符合跨界面扩散控制(Trans-interface diffusion-controlled, TIDC)粗化理论；晶界处MC型碳化物通过MC+γ→M_(23)C_6+γ′反应逐渐分解，在晶界处形成γ′相膜，包裹着MC型碳化物和M_(23)C_6型碳化物。高温拉伸实验结果表明，随热暴露时间的延长，合金的屈服强度和抗拉强度先减小后基本不变，伸长率和断面收缩率先增大后减小再增大，在热暴露5000 h后，屈服强度和抗拉强度分别减小了164和76 MPa,而在热暴露5000～24000 h时，屈服强度和抗拉强度分别稳定在750和950 MPa。

关键词(KeyWords)： 镍基高温合金;等轴Mar-M247合金;热暴露;组织演变;拉伸性能

Abstract:

Keywords:

基金项目(Foundation): 国家自然科学基金(52201102);; 长寿命高温材料国家重点实验室项目(DEC8300X202310074);; 山东省高校青年创新科技支撑计划(2020KJA002)

作者(Author): 罗超,商玉洁,高振桓,王西涛,何金珊

DOI: 10.13289/j.issn.1009-6264.2023-0482

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