Study On Forming Process And Testing Of NAO Material For Disc Brake Pad

NAO material brake Pad due to its resistance to wear,low dust,low noise and other characteristics,become the preferred car manufacturer's choosen.In China,the systematic study of its formula,process,testing is still relatively scarce.In this Paper,the hot pressing molding time is shortened to 3-4min,the structure and performance analysis of the brake Pad is used as the theoretical basis,the formulation and the forming process are studied:1.According to structure of the brake Pad and friction theory,wear theory,noise generation,damping noise reduction,sound proPagation theory analysis:the relationship between performance and its density&compressibility.2.Through binding agent,reinforcing fiber,friction additives and fillers four most effect analysis,in the formulation of the friction material adding 13%-16%group modified phenolic resin resorcinol to shorten forming time 3-4min.In the formulation of underlayer material use 50%?60%of steel fiber to strengthen the shear and optimization of noise.3 According to Differential Scanning Calorimetry analysis of phenolic resin analysis to obtain the molding temperature range of 150-170? the molding time is 3-4min.According to pre experiments,the range of molding pressure is 25MPa-35MPa.4 According to DOE orthogonal test group and MINTAB software for data analysis,the highest compressibility was 175 ? m,the minimum value was 137 ? m;the highest density was 2.56g/cm;the minimum value was 2.4g/cm.5 Through the experiment of LINK1500 Krauss obtained:density 2.4g/cm~3 cold friction coefficient? k1? k2,0.319 and 0.322 respectively,wear 37.8g;density 2.56g/cm~3 group cold friction coefficient ? k1 ? k2,0.292 and 0.303 respectively,wear 34.8g.6 Through the LINK3900 platform noise performance test:the compressibility of 175? m group can be recorded>8KHZ noise appears 12 times,and the compressibilityof 137 ?m group is 50 times.In order to obtain the optimal coefficient of friction,wear rate and noise effect,choose the molding time 3min,molding pressure 35MPa,molding temperature 150 C as the final molding Parameters.