Improving thermal stability and frictional performance of brake pad: A study on interactive effects of compression and gas release

• Systematic optimization of breathing cycle parameters using RSM-CCD. • Discovery of key interaction between compression number and gas release time. • Novel gas control method improving friction stability by 25-30%. • Simultaneous enhancement of mechanical strength (15-20%) and wear resistance. • Scientific foundation for industrial manufacturing optimization. In this study, response surface methodology (RSM) utilizing a central composite design (CCD) was employed to systematically optimize hot-pressing parameters within the manufacturing of non-asbestos organic (NAO) brake pads. This study explored the individual and interaction effects of three manufacturing parameters including compression number, compression time, and gas release time. The analysis of variance of results indicated that compression time was the most important parameter for hardness, while the normal and hot friction coefficients were mainly influenced by the interaction of compression number and gas release time. The optimization of the process parameters resulted in the optimal design point of 2 compression numbers, compression time of 4s, and gas release time of 8s. This configuration simultaneously maximized hardness and hot friction coefficient while minimizing the difference in average friction coefficients (DAFC), a key measure of friction stability. Overall, this study presents a quantitative approach for the production of high-performance brake pads, combining enhanced mechanical strength with stable tribological properties. This approach enables analytically informed optimization of the manufacturing process, thereby overcoming the limitations of conventional empirical methods.