PENGARUH PUTARAN CENTRIFUGAL CASTING DAN HEAT TREATMENT T6 VELG DARI BAHAN ALUMINIUM SCRAP TERHADAP KARAKTERISTIK PERAMBATAN RETAK FATIK

Cast wheel is a vehicle component that when in used will get dynamic load, where if loading fluktuative and much large and also repetitive, it will make failure structure. So that this product must have guaranty on failure caused by fatigue and save in used and also have useful life time. This research determined to find the effect of centrifugal casting rotation and heat treatment T6 of scrap aluminum cast wheel on fatigue crack growth characteristics. This research use scrap aluminum that was produced by remelting process on centrifugal casting rotation 400, 500, 600, 700 rpm. According to the ASTM standard (E647), this research is using Compact Test Specimen. Fatigue load is in constant amplitude condition with stress ratio R=0.1. Experimental result determined by crack length and number of cycles, and then that data will calculate to get rate of crack growth (da/dN) and difference of strength intensity factor (�K), where the data processing using incremental polynomial method (ASTM E647). Result of this research is the increasing of centrifugal casting rotation makes lower crack growth rates, where the crack growth rates of specimen with heat treatment T6 is lower than specimen without heat treatment T6