Tensile properties of directionally solidified Al--Si eutectic

Journal Article · Sat Apr 01 04:00:00 EST 1978 · Metall. Trans., A; (United States)

DOI:https://doi.org/10.1007/BF02646408· OSTI ID:6427897

Justi, S ^[1]; Bragg, R H

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1. Fairchild Research and Development, Palo Alto, CA

Al--Si eutectic alloys were directionally solidifed in a horizontal resistance heated furnace. The temperature gradient, G, ahead of the solid/liquid interface was kept fairly constant at 80/sup 0/C/cm, while the growth rate, R, was varied between 0.28 and 131 ..mu..m/s. Microstructural studies show a definite alignment of the rod-like Si at low growth rates. At growth rates higher than 14 ..mu..m/s the microstructures appear irregular, although some preferential orientation of the Si rods parallel to the growth direction can be observed. Tensile tests show higher values in both yield and ultimate strengths than was found in previous investigations, most likely due to the careful sample preparation prior to testing in the present work. The yield strength increases with the growth rate up to about 14 ..mu..m/s, and only a slight increase is observed at higher rates. The ultimate strength also increases with the growth rate, but shows less tendency toward saturation. Superposition of hardness and yield data show excellent correlation, while comparison between hardness and ultimate strength shows higher hardness than ultimate values with decreasing growth rates.

• OSTI ID: 6427897
• Journal Information: Metall. Trans., A; (United States), Journal Name: Metall. Trans., A; (United States) Vol. 9:4; ISSN MTTAB
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360102 -- Metals & Alloys-- Structure & Phase Studies
360103* -- Metals & Alloys-- Mechanical Properties
ALUMINIUM COMPOUNDS
ALUMINIUM SILICIDES
CRACKS
CRYSTAL STRUCTURE
CRYSTALS
DENDRITES
ELONGATION
EUTECTICS
MECHANICAL PROPERTIES
MICROSTRUCTURE
PHASE TRANSFORMATIONS
SILICIDES
SILICON COMPOUNDS
SOLIDIFICATION
TENSILE PROPERTIES
VICKERS HARDNESS
YIELD STRENGTH