Microstructure and fracture of SiC-particulate-reinforced cast A356 aluminum alloy composites
- Pohang Univ. of Science and Technology (Korea, Republic of). Center for Advanced Aerospace Materials
- Seoul National Univ. (Korea, Republic of). School of Materials Science and Engineering
A microstructural analysis of local microfracture of cast A356 Al-SiC{sub p} composites fabricated by permanent mold re-casting and squeeze-casting methods was made. Notch fracture toughness tests were conducted on these composites to identify critical fracture parameters using a stress-modified critical-strain criterion. The composite microstructure shows continuous networks of densely populated SiC and eutectic Si particles along the intercellular regions. Squeeze casting produces a more homogeneous structure and larger spacing of brittle particles and increases the tensile ductility and fracture toughness, while strength levels are almost identical to the re-casting case. The calculated values of the microstructurally characteristic distance l* for the re-cast and squeeze-cast composites are about 40 {micro}m, which is comparable to the average sizes of the intercellular network. However, the reference critical strain {bar {var_epsilon}}*{sub 0} for squeeze casting is larger than that for re-casting, showing a trend to higher ductility and fracture toughness.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 438554
- Journal Information:
- Metallurgical and Materials Transactions. A, Physical Metallurgy and Materials Science, Journal Name: Metallurgical and Materials Transactions. A, Physical Metallurgy and Materials Science Journal Issue: 12 Vol. 27; ISSN MMTAEB; ISSN 1073-5623
- Country of Publication:
- United States
- Language:
- English
Similar Records
Melting and casting characteristics of aluminum alloy A356-SiC particulate reinforced cast composites
A High cycle fatigue behavior of squeeze cast A356 Al/SiC{sub w} and A390 Al/SiC{sub w} MMCs