Accession Number:

AD0258399

Title:

A STUDY OF STRESS-INDUCED DELAYED FAILURE IN HIGH-STRENGTH BRASSES

Descriptive Note:

Corporate Author:

IIT RESEARCH INST CHICAGO ILL

Personal Author(s):

• CROSSLEY,F.A.
• SIMCOE,CHARLES R.

Report Date:

1960-11-10

Pagination or Media Count:

1.0

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

Descriptors:

• *BRASS
• *FAILURE(MECHANICS)
• CHLORIDES
• COOLING
• CORROSION
• CORROSIVE GASES
• CORROSIVE LIQUIDS
• FRACTURE(MECHANICS)
• GRAIN STRUCTURES(METALLURGY)
• HEAT TREATMENT
• MANGANESE ALLOYS
• MECHANICAL PROPERTIES
• RUPTURE
• SALTS
• SEA WATER
• SODIUM COMPOUNDS
• SOLUTIONS(MIXTURES)
• STRESSES
• TEMPERATURE
• TENSILE PROPERTIES
• WATER
• ZINC

Subject Categories:

Distribution Statement:

APPROVED FOR PUBLIC RELEASE