Crack healing behavior of silicon carbide ceramics
Crack healing behavior of silicon carbide ceramics
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DOI：
10.1111/j.1151-2916.2000.tb01632.x
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发表时间：
2000-11-01
影响因子：
3.9
通讯作者：
Ando, K
中科院分区：
文献类型：
--
作者：
Korous, J;Chu, MC;Ando, K
本研究重点关注三种商用碳化硅陶瓷的裂纹愈合行为。对有裂纹和无裂纹的样品在不同温度下进行热处理，并根据JIS标准通过三点弯曲试验测量其强度。测试在室温和600℃至1500℃之间的高温下进行，对于所研究的2c全等到100μm和2c全等到200μm的裂纹尺寸，愈合后的试样在室温下完全恢复强度，并且它们的强度随着愈合温度而增加。愈合样本在高温下的行为受到所用材料和测试温度的影响。一般来说，高温下强度会降低，但强度降低的程度由陶瓷的种类决定。愈合样品和光滑样品之间最重要的差异体现在材料 A 中。据观察，在 1400 摄氏度时，由该陶瓷制成的愈合样品的弯曲强度约为原始状态样品的弯曲强度值的 37%。陶瓷B还在900℃和1000℃下进行了静态疲劳测试。实验表明，愈合后试样的静态疲劳极限约为相同温度下单调弯曲强度的75%。
This study focuses on the crack healing behavior of three kinds of commercial SiC ceramics. Specimens with and without cracks were subjected to thermal treatment at different temperatures, and their strengths were measured by a three-point bending test in accordance with JIS standards. The tests were performed in air at both room temperature and elevated temperatures between 600 degrees and 1500 degreesC, The healed specimens shelved a complete recovery of strength at room temperature for the investigated crack sizes of 2c congruent to 100 mum and 2c congruent to 200 mum, and their strength increased in accordance with the healing temperature. The behavior of the healed specimens at elevated temperatures was influenced by the material used and the test temperature. Generally, the strength decreased at a high temperature, but the degree of strength reduction was determined by the kind of ceramic. The most important difference between the healed and smooth specimens was exhibited in material A. It was observed that at 1400 degreesC, the bending strength of the healed specimens made from this ceramic was about 37% of the value for specimens in an as-received state. Static fatigue tests were also performed for ceramic B at 900 degrees and 1000 degreesC. The experiment demonstrated that the static fatigue limit of a healed specimen is about 75% of the monotonic bending strength at the same temperature.