プラズマ溶融法により作製した炭化物コバルト系合金複合材料の特性とそれによる立体物の創製

抄録

In generally, particle composite alloy is fabricated by powder metallurgy. The other hand, Plasma Powder Melting(PPM) method is being put into practice for welding machine in the field of surface hardning. In this study, it is attempted to fabricate Co alloy (KCM-1)-carbide composite materials and 3-dimensional model using PPM method. The KCM-1 powder, Cr₃C₂ powder, NbC powder and WC powder are mixed respectively, which are directly melted by plasma arc in the graphite mold so as to obtain KCM-1-carbide composite materials.
The maximum bending strength of the composites reinforced with 20 wt% of Cr₃C₂ particles was 1.18 GPa, and the strength value was low in comparison with 1.34 GPa of the product without reinforcing under similar preparation conditions. In KCM-1-NbC composites, the maximum bending strength of the composite reinforced with 20 wt% of NbC particles was 1.07 GPa, NbC particles were dispersed uniformly. In KCM-1-WC composites, the strength value of this composites remarkably low in comparison with other KCM-1-carbide composites, which was caused by difference of density between KCM-1 and WC. With increasing the content of carbide, the bending modulus of these composites decreased monotonously, and the hardness of these composites increased monotonously. It has succeed in making 3-dimensional model of KCM-1-carbide composite using PPM apparatus. Plasma powder melting method will be used practically in the field of manufacturing of mold or mock up.