High-temperature wear and deformation processes in metal matrix composites

Journal Article · Tue Oct 01 00:00:00 EDT 1996 · Metallurgical and Materials Transactions. A, Physical Metallurgy and Materials Science

DOI:https://doi.org/10.1007/BF02663864· OSTI ID:417871

Singh, J; Alpas, A T ^[1]

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1. Univ. of Windsor, Ontario (Canada). Dept. of Mechanical and Materials Engineering

Dry-sliding wear behaviors of a particulate-reinforced aluminum matrix composite 6061 Al-20 pct Al{sub 2}O{sub 3} and an unreinforced 6061 Al alloy were investigated in the temperature range 25 C to 500 C against a SAE 52100 bearing steel counterface. Experiments were carried out at a constant sliding speed of 0.2 m{center_dot}s{sup {minus}1} at different test loads. The deformation behavior of the materials was studied by performing uniaxial compression tests in the same temperature range as the wear tests. Both alloys showed a mild-to-severe wear transition above a certain test temperature. In the mild wear regime, the wear rate and the coefficient of friction of the unreinforced 6061 Al decreased slightly with temperature, but the temperature had almost no effect on the wear rate and the coefficient of friction of the 6061 Al-20 pct Al{sub 2}O{sub 3} in the same regime. Particulate reinforcement led to an increase in the transition temperature and a 50 to 70 pct improvement in the wear resistance in the severe wear regime. This was attributed to the formation of tribological layers consisting of comminuted Al{sub 2}O{sub 3} particles at the contact surface. High-temperature compression tests showed that the flow strength of 6061 Al-20 pct Al{sub 2}O{sub 3} and 6061 Al decreased monotonically with temperature and both alloys exhibited a work-softening behavior at temperatures higher than the inflection point on the flow stress vs temperature curves. A power-Arrhenius type relationship was found to describe well the observed dependence of severe wear rates on the applied load and temperature. This relationship was used to calculate an apparent activation energy for wear of 87 kJ{center_dot}mol{sup {minus}1} for the particulate-reinforced composite and 33 kJ{center_dot}mol{sup {minus}1} for the matrix alloy.

• Sponsoring Organization: USDOE
• OSTI ID: 417871
• Journal Information: Metallurgical and Materials Transactions. A, Physical Metallurgy and Materials Science, Vol. 27, Issue 10; Other Information: PBD: Oct 1996
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
33 ADVANCED PROPULSION SYSTEMS
COMPOSITE MATERIALS
WEAR RESISTANCE
COMPRESSION STRENGTH
ALUMINIUM BASE ALLOYS
ALUMINIUM OXIDES
AUTOMOBILES
PARTICULATES
PARTICLE SIZE
CONCENTRATION RATIO
SLIDING FRICTION
TEMPERATURE DEPENDENCE
TRANSITION TEMPERATURE
FLOW STRESS
ACTIVATION ENERGY
STRAINS