RESEARCH DESIGNED TO EVALUATE Zr-2.5Nb AND Zr-2.5Nb-0.5Cu ALLOYS FOR DELAYED FAILURE HYDRIDE SUSCEPTIBILITY. Quarterly Report No. 3, April 15, 1963-July 14, 1963

Technical Report · Mon Jul 01 04:00:00 EDT 1963

DOI:https://doi.org/10.2172/4654966· OSTI ID:4654966

Weinstein, D; Holtz, F C

A program is in progress to determine the extent to which Zr-2.5Nb and Zr--2.5Nb-0.5Cu exhibit delayed failure under various conditions of hydrogen content, heat treatment, ambient temperature, and specimen geometry. Specimens are hydrogenated to 200 or 500 ppm in a modified Sieverts apparatus, heat treated or cold reduced (150 deg C), and then evaluated in dynamic tensile and delayed failure tests. Data presented on the ternary alloy show that the beta-quenched and aged condition promotes a high sensitivity to static fatigue fracture. At room temperature, unnotched specimens containing 500 ppm hydrogen showed ordinary dynamic tensile stress-strain properties with very good values of strength and elongation. However, at an applied stress of 95% of the yield stress, static fracture-in the absence of macroscopic plastic deformation---occurred after several hundred hours. Photomicrographs are presented showing the brittle crack propagation through the microstructure; mechanisms for such behavior are still speculative, however. (auth)

• Research Organization: Illinois Inst. of Tech., Chicago. IIT Research Inst.
• NSA Number: NSA-17-034404
• OSTI ID: 4654966
• Report Number(s): IITRI-B6005-8
• Country of Publication: United States
• Language: English

Related Subjects

BRITTLENESS
COLD WORKING
CONFIGURATION
COPPER ALLOYS
CRACKS
DEFORMATION
DUCTILITY
FAILURES
FATIGUE
GASES
HEAT TREATMENTS
HYDROGEN
MATERIALS TESTING
METALS
METALS, CERAMICS, AND OTHER MATERIALS
NIOBIUM ALLOYS
PHOTOGRAPHY
QUENCHING
SENSITIVITY
SIEVERT APPARATUS
SOLUBILITY
STRESSES
TEMPERATURE
TENSILE PROPERTIES
ZIRCONIUM ALLOYS