• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.19 no.1
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• pp.65-70
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• 2010

The effect of austempering treatment on the dynamic properties of a brake drum was investigated to primarily evaluate the potential damping advantage of an AGI (austempered gray iron) drum over a PGI (pearlitic gray iron) drum. This investigation provides valuable information for brake noise reduction since the brake drum is most often the outstanding component that generates the noise of the brake assembly. Test results show that the AGI drum provided slightly larger damping values than the PGI drum for the first few major resonances observed. A finite element model of a drum was also developed to aid in studying its dynamic behavior. A good correlation was obtained between the analytical results and the actual measurement data.

• Journal of Korea Foundry Society
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• v.41 no.6
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• pp.543-549
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• 2021

Aluminum cast iron has excellent oxidation resistance and good resistance to sulfide and corrosion. Compared to Ti and Ni alloys, it is expected to be a substitute material for structural materials and stainless steels because it is relatively inexpensive to use Fe, which is a non-strategic element. This results in a weight reduction effect of about 30% as compared to the use of stainless steel. With regard to aluminum as an alloying material, it is an element that has been widely used for the alloying of cast iron in recent years. Practical use has been delayed owing to the resulting lack of ductility at room temperature and the sharp decrease in the strength above 600℃ of this alloy, however. The cause of the weak room temperature ductility is known to be environmental embrittlement by hydrogen, and the addition of various alloying elements has been attempted in order to mitigate these shortcomings. Although alloying elements such as vanadium, chromium, and manganese are mainly used to increase the hardness and wear resistance of gray cast iron, the price of finished products containing these elements and the problems associated with alloys with this material impose many limitations.