Fracture Process during Fracture Toughness Testing in Al<SUB>2</SUB>O<SUB>3</SUB> Ceramics by AE Source Characterization
-
- Kishi Teruo
- Faculty of Engineering, The University of Tokyo
-
- Wakayama Shuichi
- Graduate Student, The University of Tokyo
-
- Shinozaki Yasuo
- Asahi Glass Co., Ltd.
-
- Kagawa Yutaka
- The Casting Research Laboratory, Waseda University
-
- Nakata Eiichi
- Nakata Seisakusho
Bibliographic Information
- Other Title
-
- AE原波形解析によるアルミナの破壊靭性試験におけるき裂進展の評価
- AE ゲンハケイ カイセキ ニ ヨル アルミナ ノ ハカイ ジンセイ シケン
Search this article
Description
The fracture process in Al2O3 ceramics was studied by Acoustic Emission (AE) source characterization technique and fractography. AE source function, which estimated the size and nucleation rate of microcracking quantitatively, was obtained by deconvolution integral of detected signals with the dynamic Green’s function of elastic medium and response function of measuring system.<BR>Three points bending tests gave the bending strength of 350 MPa and the microcracks nucleation stress of 210 MPa. On the other hand, the plane strain fracture toughness of the present material was evaluated as KIC=5.5 MPa \sqrtm by double-torsion tests.<BR>In the fracture toughness testing of a 1 inch compact tension specimen, intergranular small microcracks, of which sizes were less than 20 μm, were detected by small amplitude AE signals at 80% of final unstable fracture load, and three large microcrackings, of which sizes of 170-190 μm were evaluated by AE source characterization, were observed at over 90% of final fracture load. These large microcrackings correspond to the coalescence of small microcracks and/or transgranular cracking of coarse grains.<BR>It is concluded that final unstable fracture occurs when one of these large microcrackings has grown and reached to the critical size.
Journal
-
- Journal of the Japan Institute of Metals and Materials
-
Journal of the Japan Institute of Metals and Materials 49 (9), 707-713, 1985
The Japan Institute of Metals and Materials
- Tweet
Keywords
Details 詳細情報について
-
- CRID
- 1390282681462291840
-
- NII Article ID
- 130007339269
- 10007390474
-
- NII Book ID
- AN00187860
-
- ISSN
- 18806880
- 24337501
- 00214876
-
- NDL BIB ID
- 3044636
-
- Data Source
-
- JaLC
- NDL
- Crossref
- CiNii Articles
-
- Abstract License Flag
- Disallowed