, Volume 26, Issue 6, pp 1719-1724

Thermal fatigue of cast iron brake disk materials

Abstract

To develop cast-iron brake disks with high heat resistance to thermal shock loading, three candidate materials were developed. The main components were Fe, C, Si, Mn, Ni, Cr, Mo, Cu and Al. The mechanical and thermal properties of the candidates were measured. Thermal fatigue tests were then carried out using equipment developed by the authors. The possible temperature range of the testing equipment was 20°C ∼1500°C. Cylindrical solid specimens ϕ20 × 80 mm were heated by an induction coil and cooled in water. At an interval of 20∼30 thermal cycles, the surfaces of the specimens were examined with a digital microscope to check for thermal cracks. To quantify the total length of the cracks, an image analyzing program capable of measuring the length of cracks on micrographs was developed. It was found the fatigue lifetime of cast iron could be increased by regulating its composition and metallurgical structures.

Recommended by Editor Associate Chongdu Cho
Byeong-choon Goo received his Ph.D from the University of Franche-Comte, France and has been a principal researcher at Korea Railroad Research Institute since 1996. His main research area includes brake system, brake squeal noise, structural analysis, wheel/rail contact, fatigue, shape memory alloy.
Choong-hwan Lim received his Ph.D from the University of Science and Technology, Korea, 2010 and has been a researcher at the R&D Institute, STX Metal Co., Ltd since 2010. His main research area includes fatigue/fracture, alloys.