研究論文
TiO2粒子/AC8Aアルミニウム合金複合材の機械的性質およびTiO2と合金元素の反応の影響
2001 年 51 巻 2 号 p. 108-112
詳細
2001 年 51 巻 2 号 p. 108-112
TiO2 particles are available as reinforcements of aluminum alloy, because of their relatively low cost. But it is very difficult to make the composite with low volume fraction of TiO2, because of their fine spherical shape. Therefore, many researches had been done on TiO2–aluminum alloy composite in which the volume fraction of TiO2 was high. On the other hand, we had developed the process to make the preform with low volume fraction of TiO2 particles. Using this preform and AC8A aluminum alloy, TiO2–aluminum alloy composite in which the volume fraction of TiO2 reinforcement was relatively low was fabricated by pressure casting. Mechanical properties of this composite and the reaction between TiO2 and some elements in AC8A aluminum alloy occurred at casting and at T6 heat treating process were investigated. The results are as follows: (1) As cast state, the mechanical properties were affected only by the reinforcing effect of TiO2. Hardness and tensile strength increased with the amount of TiO2. (2) After T6 heat treating, mechanical properties were affected by the intermetallic compound that was formed by the reaction between TiO2 and some elements in AC8A aluminum alloy such as Mg or Si and this reaction occurred not only at T6 heat treating process but also at casting process. Consequently, hardness could be raised. Tensile strength at room temperature was below that of matrix, because there was no Mg that lead to the aging phenomenon. But at high temperature it was above matrix.
