แจ้งเอกสารไม่ครบถ้วน, ไม่ตรงกับชื่อเรื่อง หรือมีข้อผิดพลาดเกี่ยวกับเอกสาร ติดต่อที่นี่ ==>
หากไม่มีอีเมลผู้รับให้กรอก thailis-noc@uni.net.th
หากไม่มีอีเมลผู้รับให้กรอก thailis-noc@uni.net.th
Meechai Sriwiboon. Influences of moisture on brake pad properties and braking performance. Doctoral Degree(Mechanical and Automotive Engineering (International Program)). King Mongkut's University of Technology North Bangkok. Central Library. : King Mongkut's University of Technology North Bangkok, 2023.
Influences of moisture on brake pad properties and braking performance
Name: Meechai Sriwiboon
keyword:
Dynamic modulus
LCSH:
Disc brake
LCSH:
Automobiles
-- Brakes
LCSH:
Moisture
LCSH:
Adsorption
Abstract:
Braking system safety depends on maintaining consistent friction coefficients, but environmental moisture can significantly alter brake pad friction, leading to unpredictable braking. Conventional testing often overlooks the dynamic behavior of friction materials under varied moisture conditions. This thesis addresses this gap by investigating the influence of moisture on copper-free brake pads, focusing on sorption-desorption processes. The study examines the impact of moisture sorption on physical properties such as weight and dynamic modulus across different humidity levels. It identifies three stages of weight gain due to moisture and uses empirical equations to correlate weight gain with exposure time. The interaction between moisture and dynamic modulus reveals that increased moisture uptake leads to higher modulus values. Brake pads act like desiccants, absorbing and desorbing moisture. The results show that moisture desorption is rapid at 130°C.
Low-speed (5 km/h @ 0.1 g) and moderate-speed (50 km/h @ 0.25 g) tests were conducted to understand the frictional response under different driving conditions. Low-speed tests showed that initial humidity exposure causes a slight drop in the friction coefficient, which then stabilizes, while prolonged exposure results in a more consistent coefficient. Moderate-speed tests demonstrated that humidity exposure increases the friction coefficient with oscillations. The presence of a friction film and its sensitivity to moisture were identified as crucial factors affecting friction characteristics. Additionally, half-lifetime trends with repeated wear cycles (SAE J2707) simulate the aging process of brake pads. The dynamic modulus also increases by approximately 2% during waiting periods between tests due to moisture sorption, which impacts the friction coefficient. The study established a correlation between dynamic modulus and friction coefficient, showing that decreases in dynamic modulus correspond to increased friction coefficients.
The quantified relationships between moisture, dynamic modulus, and friction coefficients provide valuable insights for developing moisture-resistant materials, surface treatments, and innovative designs to mitigate the adverse effects of environmental conditions on braking performance. This research contributes to improving the safety and reliability of braking systems by addressing the critical influence of environmental moisture.
King Mongkut's University of Technology North Bangkok. Central Library
Address:
BANGKOK
Email:
library@kmutnb.ac.th
Name: Saiprasit Koetniyom
Role:
dissert advisor.
Email :
saiprasit.k.ae@tggs-bangkok.org
Name: Seong, Kwan Rhee
Role:
dissert advisor.
Created:
2023
Modified:
2567-07-16
Issued:
2024-07-16
วิทยานิพนธ์/Thesis
application/pdf
eng
DegreeName: Doctor of Engineering
Level: Doctoral Degree
©copyrights King Mongkut's University of Technology North Bangkok
RightsAccess:
ใช้เวลา
-0.973516 วินาที
Meechai Sriwiboon
| Title | Contributor | Type |
|---|---|---|
| Influences of moisture on brake pad properties and braking performance
มหาวิทยาลัยเทคโนโลยีพระจอมเกล้าพระนครเหนือ Meechai Sriwiboon | Saiprasit Koetniyom Seong Kwan Rhee | วิทยานิพนธ์/Thesis |
Saiprasit Koetniyom
Seong, Kwan Rhee
| Title | Creator | Type and Date Create |
|---|