Effects of thermal residual stress creeping on microstructure and tensile properties of SiC whisker reinforced aluminum matrix composite

After quenching from 600 degreesC, the isothermal treatment at 80 degreesC for SiC whisker reinforced aluminum composite was carried out. The results indicated that the dislocation state in the matrix was changed greatly, especially in the region adjacent to the interface between SiC whisker and matrix. The change of dislocation state was considered as the result of creeping caused by thermal residual stress (TRS). It was found that the thermal residual stress creeping (TRSC) treatment is a new method to reduce effectively the TRS, and increase the strengths, including micro yield strength (sigma(0.005)), yield strength (sigma(0.2)), ultimate tensile strength (UTS), of SiCw/Al composite. The mechanism of TRSC of SiCw/Al composite was given in detail. After TRSC treatment for 500 h, the UTS of pure aluminum matrix composite was up to 330 MPa. (C) 2002 Elsevier Science B.V. All rights reserved.