Synthesis and microstructure control of Mg alloy powder composites by multi-extrusion

Control of the microstructure of Mg-alloy powder composites was successfully conducted using the powder extrusion process. The resultant microstructure was analyzed as a function of the number of extrusions and area reduction ratio. The grain size ( r n ) was proportionally reduced as the number ( n ) of extrusions and the area reduction ratio ( R ) increased. The variation in grain size agreed well with the value estimated using an equation of r n = r n −1 / R 1/2 . The effect of the microstructure control on the mechanical properties will also be discussed. This investigation identified that the process was not only useful for controlling the microstructure, but also abbreviating the de-canning step among the alloy powder consolidation frequently used. Keywords Powder technology Microstructure control Composite materials Rapid solidification