Relation of defect size and location to fatigue failure in Al alloy A356 cast specimens

Book · Wed Dec 31 04:00:00 EST 1997

OSTI ID:293096

Seniw, M E; Fine, M E; Chen, E Y; Meshii, M ^[1]; Gray, J ^[2]

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1. Northwestern Univ., Evanston, IL (United States). Dept. of Materials Science and Engineering
2. Iowa State Univ., Ames, IA (United States). Center for Non-Destructive Evaluation

Because of weight and cost savings motor vehicle manufacturers are making more extensive use of cast aluminum alloys to replace forged and cast iron or steel components. The presence of pores in certain locations may reduce the fatigue life. This is of special concern for safety critical components. This study is an examination of the influence of porosity, morphology and location on the fatigue life of die cast aluminum A356 alloy specimens. The castings are first x-rayed to locate pores. Fatigue specimens were then machined from the cast test bars so that pores of various sizes are located various distances from the nearest free surface in the gage length surface. After fatigue failure the pore resulting in crack formation is carefully measured in size and distance from the surface. A statistical relation between pore size and distance from the free surface and fatigue life under constant amplitude loading was established.

• Sponsoring Organization: National Inst. of Standards and Technology, Gaithersburg, MD (United States)
• OSTI ID: 293096
• Report Number(s): CONF-970980--; ISBN 0-87339-382-1
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM BASE ALLOYS
CRACK PROPAGATION
DEFECTS
EXPERIMENTAL DATA
FATIGUE
MECHANICAL TESTS
PORE STRUCTURE
POROSITY
SIZE