Topology Optimization of Railway Brake Pad by Contact Analysis

New Transportation Research Department, Korea Railroad Research Institute(Received January 17, 2014 ; Revised March 31, 2014 ; Accepted April 4, 2014)Abstract − To stop a high speed train running at the speed of 300 km/h, the disc brake for the train should beable to dissipate enormous kinetic energy of the train into frictional heat energy. Sintered pin-type metals aremostly used for friction materials of high speed brake pads. A pad comprises several friction pins, and the topol-ogy, length, flexibility, composition, etc. have a great influence on the tribological properties of the disc brake.In this study, the topology of the friction pins in a pad was our main concern. We presented the optimization ofthe topology of a railcar brake pad with nine-pin-type friction materials by thermo-mechanical contact analysis.We modeled the brake pad with/without a back plate. To simulate a continuous braking, the pad or friction mate-rials were rotated at constant velocity on the friction surface of the disc. We varied the positions of the nine fric-tion materials to compare the temperature distributions on the disc surface. In a non-optimized brake pad, thedistance between two neighboring friction materials in the radial direction from the rotational center of the discwas not equal. In an optimized pad, the distance between two neighboring friction materials in the radial directionwas equal. The temperature distribution on the disc surface fluctuated more for the former than the latter. Opti-mizing the pad reduced the maximum temperature of the brake disc by more than 10%.Keywords − brake pad (제동패드 ), contact analysis (접촉해석 ), topology optimization (위상최적화 ), finite element(유한요소), high-speed train (고속철도)