Abrasives,such as oxides of alumina(Al),silica(Si),zirconia(Zr),chromium(Cr)etc.,are added to raise the friction level and also to remove the glaze on the disc so that surface will be rejuvenated continuously during b...Abrasives,such as oxides of alumina(Al),silica(Si),zirconia(Zr),chromium(Cr)etc.,are added to raise the friction level and also to remove the glaze on the disc so that surface will be rejuvenated continuously during braking and will contribute to maintain the desired friction level.However,these inorganic particles have less adhesion with the resin/binder and hence are easily dug out during wearing process contributing to higher wear.If efforts are made to enhance the filler‐matrix adhesion,not only the wear of friction material(FM)should reduce,the particles may stay for a longer time on the tribo‐surface of the pads to contribute fully towards controlling the coefficient of friction(μ).In the present study,alumina particles were selected for siloxane treatment to improve the filler‐matrix adhesion.Two types of eco‐friendly(free from asbestos and Cu)brake‐pads were developed using alumina as a theme ingredient(treated and untreated)keeping all the parent formulation identical.An additional type of brake‐pads without alumina particles was also developed to observe the effect of abrasive particles on the tribo‐performance.The performance properties(physical,mechanical,and tribological)of brake‐pads were compared when evaluated in identical conditions.The tribotesting was done on full‐scale brake inertia dynamometer following the procedure in Japanese automobile standard(JASO C 406).It was observed that siloxane treatment affected both friction and wear of brake‐pads in a beneficial way.Wear resistance got increased 35%for siloxane treated pads.Worn surfaces were analysed using scanning electron microscopy(SEM)and energy dispersive X‐ray(EDAX)technique.展开更多
The correlation between the wear behavior of a heavy commercial vehicle (HCV) brake liner tested under controlled laboratory conditions and that in actual field conditions is investigated.A brake liner study for frict...The correlation between the wear behavior of a heavy commercial vehicle (HCV) brake liner tested under controlled laboratory conditions and that in actual field conditions is investigated.A brake liner study for friction and wear is performed on an inertia brake dynamometer (IBD) at different temperatures (200 ℃,250 ℃,and 300 ℃) using 6000 brake actuations in a laboratory.The total wear loss of the brake liner at three different temperatures for 6000 brake actuations in IBD is found to be 1.12 mm.The actual field test is conducted on four different HCVs,namely,a city bus (CB),a high speed bus (HSB),a highway truck (HWT),and a tipper lorry (TL).These HCVs run at different terrain/traffic conditions and load conditions.When comparing the predicted life of the brake liner through the IBD test with the actual life of the brake liner in different HCVs,a vast difference is observed.Due to the large variation of liner life observed between the actual and predicted tests,an extensive field test is conducted.In the field test,the liner with identical formulation is fitted in the four types of HCVs.The predicted life of the liner using IBD is then correlated with the field test observation and a correlation factor is determined.Based on this correlation factor,the predicted life of the liner and the achieved life on the HCV are found to be fairly close.This study will be useful to design the friction material formulation and to predict the actual life of the brake liner for various HCVs.展开更多
文摘Abrasives,such as oxides of alumina(Al),silica(Si),zirconia(Zr),chromium(Cr)etc.,are added to raise the friction level and also to remove the glaze on the disc so that surface will be rejuvenated continuously during braking and will contribute to maintain the desired friction level.However,these inorganic particles have less adhesion with the resin/binder and hence are easily dug out during wearing process contributing to higher wear.If efforts are made to enhance the filler‐matrix adhesion,not only the wear of friction material(FM)should reduce,the particles may stay for a longer time on the tribo‐surface of the pads to contribute fully towards controlling the coefficient of friction(μ).In the present study,alumina particles were selected for siloxane treatment to improve the filler‐matrix adhesion.Two types of eco‐friendly(free from asbestos and Cu)brake‐pads were developed using alumina as a theme ingredient(treated and untreated)keeping all the parent formulation identical.An additional type of brake‐pads without alumina particles was also developed to observe the effect of abrasive particles on the tribo‐performance.The performance properties(physical,mechanical,and tribological)of brake‐pads were compared when evaluated in identical conditions.The tribotesting was done on full‐scale brake inertia dynamometer following the procedure in Japanese automobile standard(JASO C 406).It was observed that siloxane treatment affected both friction and wear of brake‐pads in a beneficial way.Wear resistance got increased 35%for siloxane treated pads.Worn surfaces were analysed using scanning electron microscopy(SEM)and energy dispersive X‐ray(EDAX)technique.
文摘The correlation between the wear behavior of a heavy commercial vehicle (HCV) brake liner tested under controlled laboratory conditions and that in actual field conditions is investigated.A brake liner study for friction and wear is performed on an inertia brake dynamometer (IBD) at different temperatures (200 ℃,250 ℃,and 300 ℃) using 6000 brake actuations in a laboratory.The total wear loss of the brake liner at three different temperatures for 6000 brake actuations in IBD is found to be 1.12 mm.The actual field test is conducted on four different HCVs,namely,a city bus (CB),a high speed bus (HSB),a highway truck (HWT),and a tipper lorry (TL).These HCVs run at different terrain/traffic conditions and load conditions.When comparing the predicted life of the brake liner through the IBD test with the actual life of the brake liner in different HCVs,a vast difference is observed.Due to the large variation of liner life observed between the actual and predicted tests,an extensive field test is conducted.In the field test,the liner with identical formulation is fitted in the four types of HCVs.The predicted life of the liner using IBD is then correlated with the field test observation and a correlation factor is determined.Based on this correlation factor,the predicted life of the liner and the achieved life on the HCV are found to be fairly close.This study will be useful to design the friction material formulation and to predict the actual life of the brake liner for various HCVs.
