Exceptionally high-strength (@3 GPa) aluminum alloys demonstrated by oxygen ion implantation

Conference · Wed Jan 01 00:00:00 EST 1992

OSTI ID:7253564

Follstaedt, D M; Myers, S M; Bourcier, R J; Dugger, M T

Oxygen-implanted Al surface layers are shown to have exceptional flow stresses, with values up to 2.9 GPa for 20 at.% 0. Quantitative evaluations are obtained by probing the hardness with low-load indentation and evaluating the combined response of the layer and substrate with finite element modeling. The high densities of nanometer-size oxide precipitates observed with TEM account for the high strengths through conventional dispersion hardening theory. High strength is found even after the 20% alloy is annealed at 550{degrees}C (1.2 GPa). Relatively high strengths are also found for unannealed Al implanted with as little as 5 at.% 0 (1.4 GPa). In addition, the coefficient of friction of Al and associated stick-slip adhesion are greatly reduced by 0 implantation. This work indicates that the fcc Al matrix can be precipitation hardened far beyond the strengths of current aerospace alloys ({approximately}0.5 GPa), and that conventional hardening theories can be applied to high volume fractions of nanometer-size precipitates to aid in designing new high-strength alloys. Aluminum oxide precipitates should be considered for strengthening Al alloys because of their effectiveness in blocking dislocation motion at small sizes ({approximately}l mn) and their relatively high thermal stability. Oxygen implantation should be evaluated for treatment of Al-alloy engineering components in sliding contact to improve their tribological performance.

• Research Organization: Sandia National Labs., Albuquerque, NM (United States)
• Sponsoring Organization: USDOE; USDOE, Washington, DC (United States)
• DOE Contract Number: AC04-76DP00789
• OSTI ID: 7253564
• Report Number(s): SAND-92-0213C; CONF-921183-3; ON: DE92040980
• Resource Relation: Conference: 8. international conference on TMS beam processing of advanced materials, Chicago, IL (United States), 5 Nov 1992
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM
ION IMPLANTATION
PRECIPITATION HARDENING
SURFACE TREATMENTS
ALUMINIUM OXIDES
DEPTH
FLOW STRESS
FRICTION
ION BEAMS
KEV RANGE 10-100
KEV RANGE 100-1000
LAYERS
OXYGEN IONS
SPATIAL DISTRIBUTION
TRIBOLOGY
WEAR
ALUMINIUM COMPOUNDS
BEAMS
CHALCOGENIDES
CHARGED PARTICLES
DIMENSIONS
DISTRIBUTION
ELEMENTS
ENERGY RANGE
HARDENING
IONS
KEV RANGE
METALS
OXIDES
OXYGEN COMPOUNDS
STRESSES
360106* - Metals & Alloys- Radiation Effects
360103 - Metals & Alloys- Mechanical Properties