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The developed aluminum matrix composite (AMC) is considered to be a promising material for low and high-temperature applications. Fiber reinforced AMC materials have high specific strength and modules of elasticity, together with excellent heat resistance. This experimental investigation was initiated to study the low-toughness fracture in Al 356-SiCp (silicon carbide particles) with respect to the role of the various elements of the microstructure and their probable contribution. The fracture in this composite is studied experimentally, in terms of fracture toughness testing. The low-toughness fracture is believed to be an inherent property of this composite and is caused mainly by the differential elastic and thermal properties of the two constituents. These differentials degrade the matrix alloy near the interface by its strain hardening capacity and by stress intensification introduced by the SiC particle geometry. Consequently, the matrix near the interface is subjected to high localized damage leading to premature fracture. It is found that the matrix alloy controls both flow properties and fracture in the materials investigated. It is concluded that a higher toughness composite requires a proper choice of constituent properties which dominate the stress state at the interface.

Corrosion behavior of A356-10 vol.% SiC composites cast by gravity and squeeze casting is evaluated. For this purpose, prepared samples were immersed in H2SO4solution for 2 hrs. at open circuit potential. Tafel polarization and electrochemical impedance spectroscopy (EIS) were carried out to study the corrosion resistance of composites. The results showed that corrosion resistance of composites cast by squeeze casting is higher than that of the gravity cast composites. The micrographs of scanning electron microscope (SEM) clearly showed the squeeze casting composites exhibit a good dispersion/matrix interface when compared with composites produced by gravity casting.

We have experimentally investigated the coupling between interfacial instabilities and mechanical interlocking in polymeric films consisting of the incompatible polymer pair of polypropylene/high‐density polyethylene and the compatible polymer pair of linear low‐density polyethylene/high‐density polyethylene. Our experimental results show that mechanical interlocking between the two phases can be achieved by controlling the extent of interfacial instabilities by properly selecting the initial disturbance frequency and amplitude as well as the layer depth ratio. Additionally, it has been shown that strength enhancement of the interface due to mechanical interlocking is directly proportional to the extent of wave bending in the processing apparatus. In fact, it has been demonstrated that in our test geometry maximum strength enhancement can be achieved at dimensionless wavenumbers near unity that correspond to disturbances with the largest growth rates. Overall, it has been shown that mechanical interlocking induced by a controlled amount of interfacial instabilities (i.e., based on knowledge of the stability of the interface and growth/decay rate of interfacial waves) can significantly increase the interfacial strength of two layer polymeric structures consisting of incompatible and compatible polymer pairs. Moreover, this effect is more pronounced in incompatible polymer pairs that possess negligible interfacial strength in absence of mechanical interlocking.