A STUDY OF STRESS-INDUCED DELAYED FAILURE IN HIGH-STRENGTH BRASSES
Abstract
THE MOST IMPORTANT FACTOR IN THE DELAYED FAILURE OF SAE 430B MANGANESEBRONZE APPEARED TO BE THE EFFECTS OF RAPID COOLING FROM HIGH TEMPERATURES. SENSITIVITY TO THIS FACTOR APPEARS TO INCREASE WITH INCREASING ZN EQUIVALENCE WHEN COMPOSITION VARIATION IS CONSIDERED. COARSE GRAIN SIZE ALSO APPEARS TO INCREASE SENSITIVITY. THE ALLOY IS NOTCH SENSITIVE. IN THE COURSE OF DYNAMIC TENSILE TESTS CRACKS OPENED UP ON THE SURFACE. AT TEMPERATURES OF 25 AND 90 C, WATER PROMOTED THE PROPAGATIONOF THESE CRACKS TO FAILURE IN ALL OF THE MATERIAL CONDITIONS TESTED. AT90 C, SALT SOLUTION PROMOTED CRACK PROPAGATION IN ALL OF THE MATERIAL CONDITIONS; BUT AT 25 C, CRACK PROPAGATION WAS FACILITATED ONLY INTHE COARSE-GRAINED, HIGH TEMPERATURE QUENCHED MATERIAL. COMPARISON OFTHE RESULTS FROM DYNAMIC AND STATIC TENSILE TESTS SUGGESTS THAT THE AQUEOUS MEDIA HAVE INFLUENCE ON TWO FACTORS: (1) THE STRAIN REQUIREENT FOR CRACK INITIATION AT THE SURFACE AND (2) THE ENERGY REQUIREMENTFOR CRACK PROPAGATION
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 10, 1960
- Accession Number
- AD0258399
Entities
People
- Charles R. Simcoe
- F.a. Crossley
Organizations
- IIT Research Institute