Fracture Analysis and Material Improvement of Brake Discs

Abstract

Using a steel material for forging, development of new discs for the next Shinkansen had been started. However, a fracture in a forged disc occurred in a durability test. Subsequently, from the viewpoint of higher fracture toughness, material improvement to an extent sufficient to withstand such a fracture due to tensile residual stress accumulation became the goal of further development. Among the candidate materials, modified AISI 4330 was selected and evaluated in laboratory and field tests. Following the subsequent durability test in the field, modification for bolt sticking and forging formability was conducted. This new brake disc, which proved to be satisfactory for Shinkansen vehicles, is capable of running at high speeds of more than 270 km/h and therefore suitable for current vehicles such as the Nozomi and Tsubasa.

Finite Element Analysis of Thermal Stresses in a Pad-Disc Brake System (A Review)

“…Based on observation with a scanning electron microscope three types of structures of the material were identified defining the successive steps of cracks growth in the disc brake in article (Sakamoto and Hirakawa, 2005). The impact of the chemical composition to improve the properties of the materials used for the brake discs was discussed.…”

Ten Years Educational Activities Using Electric Vehicles at Kochi University of Technology: 2nd Report of Laboratory Activities in 2000-2006

“…They are ecological and material strength research activities. The author used to work with a steel and iron manufacturer and had been engaged in development of railroad vehicle products such as axle, wheel, and bogie truck frame [Sakamoto, 2007a;Sakamoto, 2007b;Sakamoto et al, 2005c;Sakamoto et al, 2003d]. After joining with the university, themes on ecological or renewable energy and design education [Sakamoto et al, 2007e, Sakamoto et al, 2003f, Sakamoto et al, 2003g] have been focused.…”

Effects of Fe addition on the mechanical and thermo-mechanical properties of SiC/FeSi2/Si composites produced via reactive infiltration

“…minimum braking distance or maximum deceleration, in planes, trains or automobiles demand the use of novel materials. Classical brake disks, made of cast irons with variable carbon contents [1][2][3][4] are no longer useful for ultimate applications, since their high density and use-induced microstructural transformations [5][6][7] severely shorten their lifetime. Carbon-carbon composites (C/C) have been widely used as an alternative for high wear applications such as brake discs for their excellent thermal properties, their low density, and their sufficient mechanical properties [8][9][10].…”