Basic Study on the Toughening of Ceramics

陶瓷增韧的基础研究

• 批准号: 61470073
• 负责人: NISHIDA Toshihiko
• 金额: $ 2.18万
• 依托单位: Kyoto Institute of Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1986
• 资助国家: 日本
• 起止时间: 1986 至 1987
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-61470073/
• 关键词: Ceramics; Fracture toughness; Toughening; Wisker; Fracture energy; 耐火物; 複合材料; Rー曲線; 線形破壊力学; 弾塑性破壊力学; ウイスカー強化セラミックス; 引き抜き効果; シェブロンノッチ; 高温破壊; エンジニアリングセラミックス

As abasic study on the improvement of the brittleness in ceramic materials,(1) Studies on manufactural processing of toughend ceramics, and (2) Reconsidering studies on the evaluation of fracture toughness K_<IC> for brittle materials, were investigated.Sic wisker reinforced MgO or AlN ceramics were hot-pressed. K_<IC> values of thise ceramics were a little larger than those of hot-pressed MgO or AlN without wisker at lower temperature. On the otherhand, the values increased remarkably at the temperature range above 1000C and 1400C for MgO and AlN composite respectivery, due mainly to wisker pull-out mechanisum.K_<IC> of stractural ceramics such a sAl_2O_3,Si_3N_4 Sic was evaluated by SEPB technique. The values obtained from each measurment showed a good reproducibillity for Al_2O_3 and SiC. Si_3N_4, however, the values scattered a little. The causes of the scattering were discussed on the observation of inclined precrack front and deflected fracture surface.The fracture mechanics for toughened ceramics such as refractory materials were remarked. K_<IC> derived from linear fracture mechanics rcipe may be meanless for the toughened ceramics, bacause there might be a considerable difference between the fracture resistances for crack initiation and propagation. Some experimental techniques were tried to some refractories and castable composit.

作为改善陶瓷材料脆性的基础研究，进行了(1)增韧陶瓷制造工艺的研究，(2)脆性材料断裂韧性K_<IC>评价的再思考研究。采用热压法制备了SiC晶须增强MgO或AlN陶瓷。该陶瓷在较低温度下的K_<IC>值略大于热压无晶须的MgO或AlN。另一方面，MgO和AlN复合材料在高于1000℃和1400℃的温度范围内的值显着增加，这主要是由于晶须拉出机制。通过SEPB技术评估了sAl_2O_3、Si_3N_4 Sic等结构陶瓷的K_<IC>。 Al_2O_3 和 SiC 的每次测量值均显示出良好的重现性。然而，Si_3N_4 的值有点分散。通过观察倾斜的预裂纹前沿和偏转的断裂面，讨论了散射的原因。对耐火材料等增韧陶瓷的断裂力学进行了评述。由线性断裂力学公式导出的K_<IC>对于增韧陶瓷来说可能没有意义，因为裂纹萌生和扩展的断裂抗力之间可能存在相当大的差异。对一些耐火材料和浇注料复合材料进行了试验技术的尝试。

项目成果

西田俊彦 他: "セラミックスの力学的特性評価" 日刊工業新聞社, 250 (1986)

西田敏彦等：“陶瓷机械性能的评价”日刊工业新闻社，250（1986）

Toshihiko Nishida: "Evaluation of Fracture Toughness for Stractural Ceramics using SEPB Technique" Journal of the Ceramic Society, Japan.

Toshihiko Nishida：“使用 SEPB 技术评估结构陶瓷的断裂韧性”，日本陶瓷学会杂志。

西田俊彦: 材料.

西田俊彦：材料。

西田俊彦: 材料科学.

西田俊彦：材料科学。

Toshihiko Nishida: "Fracture Behaviour of Castable Cement" Journal of the Ceramic Society, Japan.

Toshihiko Nishida：“浇注水泥的断裂行为”日本陶瓷学会杂志。