難燃性マグネシウム合金の結晶粒径に及ぼす摩擦攪拌処理条件の影響

抄録

With the problems of exhaustion of fossil fuels and global warming, weight reduction is required to improve the fuel efficiency of automobiles and railway vehicles. Weight reduction is expected by using magnesium alloys, the lightest material among ones for practical structural use. However, magnesium alloys are inferior to conventional materials in mechanical characteristics. Magnesium alloys are known to be strengthened by grain refinement. In friction stir process (FSP), which is one of the methods of grain refinement, a workpiece is subjected to severe plastic straining by a highspeed rotating tool, and mechanical characteristics in the agitation section can be improved by grain refinement. In this study, FSP is applied to a flame resistant magnesium alloy whose flame retardancy has been improved by adding Ca, and the influence of FSP conditions on the grain size is examined.