This content is not included in your SAE MOBILUS subscription, or you are not logged in.
Changing Properties of Brake Pads and Discs during Brake Testing
ISSN: 0148-7191, e-ISSN: 2688-3627
Published October 05, 2020 by SAE International in United States
This content contains downloadable datasetsAnnotation ability available
Earlier publications show that brake pad physical properties such as hardness, modulus and natural frequencies continue to increase at room temperature over a period of 12 months and that the changes are faster during the first 3 - 6 months. The current investigation was undertaken to see how the properties might change during testing for the pads as well as for the discs. Low-copper and copper-free formulations were tested on pickup truck and passenger car brakes. In all cases, the dynamic modulus and natural frequencies are found to decrease (not increase) after the SAE J2522 performance testing, indicating that the stiffness of the pad and that of the disc decrease faster than the mass loss due to wear. Also, the inboard pad and the outboard pad change at two different rates. Questions arise on what properties to measure for quality assurance and when to measure in light of these changing properties as well as the fact that the relationship between the initial properties and the later properties is not well established and that the relationship between the properties and brake friction/NVH is also not well established.
CitationSriwiboon, M., Tiempan, N., Kaewlob, K., and Rhee, S., "Changing Properties of Brake Pads and Discs during Brake Testing," SAE Technical Paper 2020-01-1628, 2020, https://doi.org/10.4271/2020-01-1628.
Data Sets - Support Documents
|[Unnamed Dataset 1]|
|[Unnamed Dataset 2]|
|[Unnamed Dataset 3]|
|[Unnamed Dataset 4]|
|[Unnamed Dataset 5]|
|[Unnamed Dataset 6]|
|[Unnamed Dataset 7]|
|[Unnamed Dataset 8]|
|[Unnamed Dataset 9]|
|[Unnamed Dataset 10]|
|[Unnamed Dataset 11]|
|[Unnamed Dataset 12]|
|[Unnamed Dataset 13]|
|[Unnamed Dataset 14]|
|[Unnamed Dataset 15]|
|[Unnamed Dataset 16]|
|[Unnamed Dataset 17]|
|[Unnamed Dataset 18]|
|[Unnamed Dataset 19]|
|[Unnamed Dataset 20]|
|[Unnamed Dataset 21]|
- Sriwiboon, M., Tiempan, N., Kaewlob, K., and Rhee, S. , “Disc Pad Physical Properties vs. Porosity: The Question of Compressibility as an Intrinsic Physical Property,” SAE Int. J. Mater. Manf. 11(1):57-78, 2018, https://doi.org/10.4271/05-11-01-0007.
- Sriwiboon, M., Rhee, S.K., Tiempan, N., and Kaewlob, K. , “Aging Effect on Disc Pad Properties,” SAE Technical Paper 2019-01-2108, 2019, https://doi.org/10.4271/2019-01-2108.
- Sriwiboon, M., Tiempan, N., Kaewlob, K., and Rhee, S. , “Non-Asbestos Organic (NAO) Disc Pad Wear Behaviour: Divergence of Thickness Loss and Weight Loss,” SAE Technical Paper 2018-01-1866, 2018, https://doi.org/10.4271/2018-01-1866.
- Rathee, A., Sharma, D.K., Singh, S., and Rhee, S.K. , “Divergence of Thickness Loss vs. Weight Loss, Friction and Wear Behavior of Heavy Truck Brake Blocks: Development of a New Test Procedure for the Chase Tester,” SAE Technical Paper 2019-01-2107, 2019, https://doi.org/10.4271/2019-01-2107.
- Wikipedia , “Natural Frequency.”
- Wikipedia , “Chegg Study - Stiffness.”
- Lee, S., Jeon, J., Kim, S., Kim, S. et al. , “A Study of Low-Frequency and High-Frequency Disc Brake Squeal,” SAE Technical Paper 2016-01-1944, 2016, https://doi.org/10.4271/2016-01-1944.
- Lee, S., Jeon, J., Jeong, J., Park, B. et al. , “Disc Brake Squeal vs. Disc Pad Compressibility - Caliper Stiffness Interactions: Low-Frequency Squeal and High-Frequency Squeal vs. Differential Pad Wear,” SAE Technical Paper 2017-01-2528, 2017, https://doi.org/10.4271/2017-01-2528.
- Otto, J., Ostermeyer, G., and Rhee, S. , “On the Wear Dependence of Low-Frequency and High-Frequency Brake Squeal,” SAE Technical Paper 2018-01-1902, 2018, https://doi.org/10.4271/2018-01-1902.
- Andriollo, T., Vedel-Smith, N., Thorberg, J., and Hattel, J. , “Internal Casting Stresses and Dimensional Stability,” Cast Iron Science and Technology, Volume 1A, ASM Handbook, 2017, doi:10.31399/asm.hb.v01a.9781627081795.
- Shin, H., Jang, G., Kim, J., Kim, H. et al. , “The Effect of Residual Stress on the Distortion of Gray Iron Brake Discs,” Journal of Materials Engineering and Performance 22:1129-1135, 2013.