Fabrication of alumina/aluminum/silicon composites by reaction between aluminum and Amakusa pottery clay

Alumina/aluminum/silicon composites were fabricated by reaction between aluminum and Amakusa pottery clay ("Amakusa"). On heating the "Amakusa" powder compact contacting with aluminum, reaction occurred above 1473 K, Sintering the "Amakusa" compact at 1623 K before the reaction lowered the reaction temperature to 1173 K and increased the reaction rate, Three kinds of composites obtained from the "Amakusa" compact, the sintered body and the sintered body containing alumina powder (20 mass%), named C (A), C (B) and C (C), respectively, were characterized, They contained similar to 10 vol% of metal phase and showed microstructure with three-dimensionally interconnected metal phase, Their relative densities were 94-99%. The bending strength of the composites, C (ii), C(B), and C(C), were 143, 210 and 240 MPa, respectively, Their fracture toughnesses were 2.3, 3.9, and 4.3 MPa.m(1/2), respectively.