Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1580705 | Materials Science and Engineering: A | 2009 | 6 Pages |
Abstract
Crack growth rates (CGR's) were determined under sustained and cyclic loads using 17 mm compact tension and cantilever beam specimens taken from Zr-2.5Nb tubes charged to 6-100 ppm H. The cyclic load effect on the CGR was investigated at 250 °C where load ratios, R were varied from 0.13 to 1 with a constant Kmax. Under sustained loads, the CGR of the Zr-2.5Nb tube increased with supersaturation of hydrogen, ÎC and leveled off above 20-35 ppm H of the ÎC. Under cyclic loads with 1 cycle/min, the CGR at 250 °C decreased with decreasing R: 3.2 Ã 10â8 m/s at R = 1 and 4.8 Ã 10â9 m/s at R = 0.13. The striation spacing, corresponding to the critical hydride length, decreased with decreasing R, indicating easier cracking of the hydrides under cyclic loads. The decreased CGR under cyclic loads and its dependence on the ÎC are discussed using Kim's delayed hydride cracking model.
Related Topics
Physical Sciences and Engineering
Materials Science
Materials Science (General)
Authors
Young S. Kim, Albertas Grybenas,