在KOBO挤出和老化后,在中间温度下使用SiCp强化ZK60合金的变试引起的微结构变化
Yang-Yang Wang1, Chen Jia2, Min Xu2
1School of Engineering, Xi'an Siyuan University, Xi'an 710038, China.
Materials (Basel, Switzerland)
|May 27, 2023
概括
这项研究研究了ZK60合金和ZK60/SiC复合材料在高温下的爬行. 谷物边界滑动被确定为一个关键机制,微观结构变化影响爬行行为和故障模式.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 金工业是金工业的一个方面.
背景情况:
- ZK60合金和ZK60/SiC颗粒复合材料是先进的材料,具有需要高温强度的潜在应用.
- 了解爬行行为对于预测这些材料在高温压力下的长期性能和耐用性至关重要.
研究的目的:
- 研究ZK60合金和ZK60/SiCp复合材料的爬行性能.
- 为了确定温度和压力对爬行机制的影响.
- 分析爬行过程中的微观结构演变和故障机制.
主要方法:
- 在ZK60合金和ZK60/SiCp复合材料上,在10-80MPa应力范围内,在200°C和250°C进行了爬行测试.
- 使用光学显微镜和扫描电子显微镜 (SEM) 进行了微结构分析.
- 计算了真实应力指数和明显激活能量,以确定爬行机制.
主要成果:
- 两种材料的真应力指数在1.6-2.3之间.
- 显而易见的激活能量表明谷物边界滑动 (GBS) 是主要的机制.
- 微结构分析揭示了在不同温度和应力下不同的强化机制 (双,剪带,曲带,滑带),滑带在250°C时延迟了GBS.
- 失败的原因是围绕着降水和SiC颗粒的腔核形成.
结论:
- ZK60合金和ZK60/SiCp复合材料的爬行行为受到温度和应力的影响.
- 谷物边界滑动是一种主要的爬行机制,由微观结构特征 (如滑带) 调节.
- 颗粒和沉接口作为腔内核的地点,导致爬行失败.
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