Interfacial reaction in squeeze cast
SiCw/AZ91 composites withdifferent binders
SiCw/AZ91 composites withdifferent binders
(1. School of Materials Science and Engineering,
Harbin Institute of Technology, Harbin 150001, P.R.China;
2. Department of Metallurgical Engineering,
Tokyo Institute of Technology, Tokyo152, Japan)
Harbin Institute of Technology, Harbin 150001, P.R.China;
2. Department of Metallurgical Engineering,
Tokyo Institute of Technology, Tokyo152, Japan)
Abstract: The whisker/matrix interfaces in squeeze cast SiCw/AZ91 composites with different binders (silica binder, acid aluminum phosphate binder and without binder), were studied by transmission electron microscopy (TEM) and high resolution electron microscopy (HREM). The SiCw／AZ91 interface is very clean in the composites with no binders. For the composites with acid aluminum phosphate binders or silica binders, there exists fine discrete interfacial reaction products MgO at the interface, and a definite orientation relationship between MgO and SiCw. The interfacial reaction products MgO is unevenly distributed at different parts of the composite ingot with silica binder, and mainly distributed to the interface at the side part of the composite cylinder. While in the SiCw/AZ91 composite with acid aluminum phosphate binder, MgO particles are distributed evenly at the interface in almost all the parts of the composite ingot.
Key words: SiC whisker; magnesium alloy; composites; binder; interfacial reaction