液相烧结碳化与氧化和氧化的热导率增加
Ziting Yuan1, Yuhong Chen1,2, Fan Yang1
1College of Materials Science & Engineering, North Minzu University, Yinchuan 750021, China.
Materials (Basel, Switzerland)
|February 27, 2026
概括
使用烧结辅助器的碳化 (SiC) 陶的火花等离子烧结 (SPS) 显著提高了导热性. 较高的温度促进异常的谷物生长,这是改善SiC的关键.
科学领域:
- 材料科学 材料科学 材料科学
- 陶工程 陶工程 陶工程
背景情况:
- 碳化 (SiC) 陶是先进的材料,具有需要高热导率的潜在应用.
- 优化SiC的微观结构对于提高其热物理性质至关重要.
研究的目的:
- 调查烧结温度对SiC陶微观结构和导热性的影响.
- 为了确定通过火花等离子烧结制备的SiC中颗粒大小和导热率之间的关系.
主要方法:
- 使用α-SiC粉末与氧化和氧化作为烧结辅助剂制备SiC陶.
- 在1900,2000和2050°C的温度下进行火花等离子体烧结 (SPS),停留时间为10分钟.
- 微观结构分析以检查颗粒大小和形态;测量导热性.
主要成果:
- 烧结温度显著影响了谷物生长,其尺寸从0.54微米增加到17.59微米.
- 随着烧结温度的上升,热导率从122.4W/m·K增加到231.8W/m·K.
- 升高的温度加速了溶解-沉,导致异常的谷物生长和热导率的增加.
结论:
- 颗粒大小是控制SiC陶导热率的主要因素.
- 较大的SiC颗粒降低了颗粒边界密度和界面热阻,增强了声子传输.
- 优化SPS参数,特别是温度,对于定制SiC陶热性能是有效的.
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