陶瓷材料断裂韧性测试新技术——静态爆破剂预制裂纹的研究

A New Technique of Evaluation of Fracture Toughness for Ceramic Materials-the Static Expansion Method Precracking

准确测试陶瓷材料断裂韧性Ｋ１Ｃ的关键是预制具有原生裂纹的试样。本文以单边切口梁法测试Ｋ１Ｃ为基础，提出了一种简便而有效的陶瓷材料原生裂纹的预制方法———静态膨胀法。研究结果表明：静态膨胀法中裂纹的扩展是稳态的：通过调节影响微裂纹产生与扩展的多种因素，可以准确地控制裂纹扩展的深度，预制出合适的原生裂纹，为准确评价结构陶瓷的断裂韧性提供了一种有效可行的方法。

Specimens with natural sharp cracks are important for measuring the fracture toughness K 1C of ceramic materials. In this paper, a new method, the static expansion (SE) method to precrack is devised based on the single through beam method. The results show that the crack growth is stable in SE method and the precrack length of specimens can be accurately controlled by adjusting the factors effecting on the crack introduction and crack propagation. It provides an effective means to evaluate accurately the fracture toughness of ceramic materials.