金属粉末レーザ積層造形により製造されたAl-10Si-0.4Mg/SiC複合体の熱処理と微細組織変化

抄録

This work examined the effect of artificial aging (AA), solution heat treatment (SHT) and T6 (SHT followed by AA) heat treatment on the microstructural evolution and mechanical properties of Al-10Si-0.4Mg (mass%)/SiC composites fabricated by Selective Laser Melting (SLM) method. The microstructure of the As-build specimen consisted of an α-Al (fcc) phase, a (α-Al-Si) eutectic phase, SiC particles and needle-like Al₄SiC₄ compound. SHT results in coarsening of Si particles from eutectic phase. While, fine Mg₂Si was supposed to be precipitated by AA. The spheroidizing of Al₄SiC₄ was partially enhanced by SHT. As-build specimen exhibited high compressive strength (＝564 MPa), and the strength was decreased by SHT process due to coarse Si particles. Interestingly, we found that AA improved Young's modulus of the Al-10Si-0.4Mg/SiC composites.