Processing and response of aluminum-lithium alloy composites reinforced with copper-coated silicon carbide particulates

Journal Article · Sun Feb 01 04:00:00 EST 1998 · Journal of Materials Engineering and Performance

DOI:https://doi.org/10.1361/105994998770348052· OSTI ID:616127

Khor, K A; Cao, Y; Boey, F Y.C. ^[1]; Hanada, K; Murakoshi, Y ^[2]; Sudarshan, T S ^[3]; Srivatsan, T S ^[4]

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1. Nanyang Technological Univ. (Singapore). School of Mechanical and Production Engineering
2. AIST, Tsukuba (Japan). Mechanical Engineering Lab.
3. Materials Modification Inc., Fairfax, VA (United States)
4. Univ. of Akron, OH (United States). Dept. of Mechanical Engineering

Lithium-containing aluminum alloys have shown promise for demanding aerospace applications because of their light weight, high strength, and good damage tolerance characteristics. Additions of ceramic reinforcements to an aluminum-lithium alloy can significantly enhance specific strength, and specific modulus while concurrently offering acceptable performance at elevated temperatures. The processing and fabrication of aluminum-lithium alloy-based composites are hampered by particulate agglomeration or clustering and the existence of poor interfacial relationships between the reinforcing phase and the matrix. The problem of distribution of the reinforcing phase in the metal matrix can be alleviated by mechanical alloying. This article presents the results of a study aimed at addressing and improving the interfacial relationship between the host matrix and the reinforcing phase. Copper-coated silicon carbide particulates are introduced as the particulate reinforcing phase, and the resultant composite mixture is processed by conventional milling followed by hot pressing and hot extrusion. The influence of extrusion ration and extrusion temperature on microstructure and mechanical properties was established. Post extrusion processing by hot isostatic pressing was also examined. Results reveal the increase in elastic modulus of the aluminum-lithium alloy matrix reinforced with copper-coated SiC to be significantly more than the mechanically alloyed Al-Li/SiC counterpart. This suggests the possible contributions of interfacial strengthening on mechanical response in direct comparison with a uniform distribution of the reinforcing ceramic particulates.

• OSTI ID: 616127
• Journal Information: Journal of Materials Engineering and Performance, Journal Name: Journal of Materials Engineering and Performance Journal Issue: 1 Vol. 7; ISSN 1059-9495; ISSN JMEPEG
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
36 MATERIALS SCIENCE
AEROSPACE INDUSTRY
ALUMINIUM ALLOYS
COMPOSITE MATERIALS
FABRICATION
INTERFACES
LITHIUM ALLOYS
MECHANICAL PROPERTIES
MICROSTRUCTURE
SILICON CARBIDES