Failure analysis of aluminum alloys casting in four-wheels vehicle rims

Abstract

Abstract The small industry of casting aluminum alloy produces four-wheeled motorized tire rims that have been used in various vehicles. However, in general, these products do not yet have the quality and safety guarantees required by SNI 1896: 2008. Failure analysis research must be conducted to examine the causes of failure. The research method is to compare the products of small industry with products made by local and imported products by analyzing test results. Observation on visual and penetrant test showed porosity at the center of the rim. Tensile strength was (111-145)MPa much lower than local and imported product (260-285)MPa. The impact value was (500-570)kg (rim broken) and this value was lower than the SNI requirement (936 kg). The content of iron element was (0.401-0.433)%, this content was higher than local and imported rim (0.120-0.135)%. This element will cause a tendency to form micro crack and reduce the strength of mechanical properties. Microstructure observation showed a dendritic structure, porosity, and AlFeSi phase resembles needles. It was concluded that the failure of this rim product is caused by the material and the casting process. Small industries should make efforts to know the casting defects aiming to minimize product failure.