| Title |
Fabrication and Characterization of Squeeze Cast AC4A Al / TiNi Shape Memory Composites |
| Authors |
김부섭(B . S . Kim) ; 조영서(Y . S . Cho) ; 최일동(I . D . Choi) ; 안득만(D . M . An) ; 조경목(K . M . Cho) ; 박익문(I . M . Park) |
| Abstract |
Reinforcement of shape memory alloys within metal matrix reveals compressive residual stresses in the matrices resulting in improved tensile properties of the composites. In the present study, Al/TiNi shape memory composites were fabricated by the squeeze casting technique. Optimal fabrication conditions for squeeze casting were obtained experimentally. Fairly good microstructure and matrix/reinforcement bonding observed in the squeeze cast Al/TiMi composites. Tensile tests of the composites were carried out above Ar(austenite finish temperature) which was found from DSC analysis. The amount of prestrain to induce the compressive residual stress in Al matrix and the recovery force of the TiNi were determined from tensile curves of TiNi wire. Improved strength of the composite due to TiNi reinforcement as well as compressive residual stresses in Al matrix was identified. It was found that the total interfacial area between matrix and reinforcement which depends on the wire diameter also affected the strength enhancement. |