DETERMINATION OF DA/DN-DELTA-K1 CURVES FOR SMALL CRACKS IN ALUMINA IN ALTERNATING BENDING TESTS

被引：57

作者：

FETT, T ^{[1
]}

MARTIN, G ^{[1
]}

MUNZ, D ^{[1
]}

THUN, G ^{[1
]}

机构：

[1] UNIV KARLSRUHE,INST ZUVERLASSIGKEIT & SCHADENSKUNDE MASCHINENBAU,W-7500 KARLSRUHE,GERMANY

来源：

JOURNAL OF MATERIALS SCIENCE | 1991年 / 26卷 / 12期

关键词：

D O I：

10.1007/BF01124680

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

Crack-growth relations under cyclic fatigue conditions are mostly determined for long cracks. In order to determine da/dN-DELTA-K curves for small cracks from lifetimes under cyclic load a procedure has been derived which is based on a method usually applied to subcritical crack growth. To prove the cyclic effect and to demonstrate the procedure in detail, measurements were carried out on an Al2O3-ceramic in bending with an R-ratio of R = -1 and two types of relatively small cracks, namely natural cracks and Knoop-cracks. It was found that both crack types exhibit the same da/dN-DELTA-K relation. The exponent of the Paris law for fatigue crack growth is significantly different from the exponent of the power law for subcritical crack growth.

引用

页码：3320 / 3328

页数：9