The distribution of silicon carbide (SiC) particulate in the matrix of an A380–SiC(p) composite of a die-cast chain wheel depends upon the size of the SiC particulate, the core pin materials and the plunger velocity during the die-casting process. SiC particulate (13 μm) is distributed homogeneously in the die-cast product and the particulate content remains the same after the casting process. However, the 60 μm SiC particulate causes particulate segregation and settling in the shot biscuit and does not pass easily through a gate of 1.0 mm thickness. Further, it reduces the particulate content in the die-cast product and causes inhomogeneous particulate distribution in the teeth of the chain wheel. Using SKH 4A steel as a core pin, the SiC particulate was distributed very uniformly around the screw bolt holes of the product. In contrast, SiC-free zones were observed around the screw bolt holes when using sintered tungsten carbide (WC) as a core pin. A faster plunger velocity of 3.8 m s−1 or a slower velocity of 0.3 m s−1 result in some SiC-free zones in the cast product.
Relation:
Journal of materials processing technology 84(1-3), pp.236-246