Analysis of Hot Spots Evolution on Brake Disc Using High-Speed Infrared Camera

Abstract

The hot spot generation has been considered as the main degradation mechanism in railway brake disc. Therefore, the understanding of hot spots, also called hot judder, which is undesirable low frequency vibrations developed by non-uniform contact area between brake pad material and brake disc, is important for a better understanding of material design as well as enhancement of materials properties in railway brake disc. Also, infrared (IR) thermography is a powerful NDE technique for the characterization of thermal phenomenon in engineering components and/or systems including engineering materials. The high-speed IR camera provides the measurement of temperature change during brake operation as well as the images of temperature contour on the brake disc surface. In this investigation, damage evolution due to generation of hot spots on railway brake disc was investigated using the infrared thermography method. Moreover, based on obtained thermographic images of hot spots, the hot spots and thermal damage of railway brake disc during braking operation were qualitatively analyzed.

Non-Destructive Characterization of Railway Materials and Components with Infrared Thermography Technique

“…In this study, two types of railway materials were used: axle railway steel for diesel electric locomotives and glass fiber-reinforced epoxy polymer matrix composites (PMCs) for railway bogies. In the case of railway steel materials, the tensile specimens for this study were prepared by machining on the axle of a diesel electric locomotive [6,7], and dog-bone flat specimens were prepared from the actual axle. For PMC samples, the actual tensile specimens were obtained from E-glass fiber-reinforced epoxy composites.…”

“…The initial braking speed (km/h) and the sequence of braking tests were as follows: 65,35,95,65,110,95,95,35,110,65,65,95,110,110,35,35, and 65 km/h. Braking tests for this study were performed using a full-scale dynamometer operated at the Korea Railroad Research Institute (KRRI) [6,11,12].…”

“…Various types of non-destructive evaluation (NDE) technologies are used during the regular maintenance of railway vehicles including ultrasonic testing (UT), magnetic particle testing (MT), radiography (RT), and infrared (IR) thermography [1][2][3][4][5]. Among the possible NDE technologies, infrared (IR) thermography is a relatively new technology in the field of railway maintenance and is an advanced non-destructive evaluation technique based on infrared detection [5][6][7][8][9][10]. In particular, infrared thermography technology is an advantage, providing fast full field and real-time inspection as well as contactless mode.…”

Selected Simulation and Experimental Studies of the Heat Transfer Process in the Railway Disc Brake in High-Speed Trains

“…Numerous works on the tribology of friction pairs have been presented, including the study [26]. The authors of [10] showed the results of tests obtained on actual objects of the rail vehicle braking system, showing the phenomenon of generating hot areas during the tribological tests of friction pairs of rail brakes. Such phenomena reduce the braking effectiveness and cause chemical changes in the structure of brake elements made of organic materials.…”