A significant fraction of the non-exhaust particulate matter emissions from vehicular traffic comprises fine particles from the wear debris of brake pads and discs.Recent studies have shown that these emissions can be...A significant fraction of the non-exhaust particulate matter emissions from vehicular traffic comprises fine particles from the wear debris of brake pads and discs.Recent studies have shown that these emissions can be consistently reduced by using wear resistant disc coatings.This study thoroughly analyses the debris produced by a low-met brake pad,which is dyno-bench tested against both cast iron and WC-CoCr-coated brake discs.To achieve this,particles in the size range of 2.5|im to 30 nm were collected and characterized.The results showed a consistent reduction in the particle emission as well as in the concentration of iron oxides,which are mainly released from the disc tribo-oxidation in the coated disc.Furthermore,a few tungsten carbides,released from the coating,were also observed in the wear fragments.The results of this study can be useful for improving the protective coating and consequently help in reducing particulate matter emission further.展开更多
The topography and distribution of wear particles produced in the wear process containmuch information about the wear status. Fractal geometry is applied in this paper to describe thewear particle accumulation in orde...The topography and distribution of wear particles produced in the wear process containmuch information about the wear status. Fractal geometry is applied in this paper to describe thewear particle accumulation in order to characterize the wear status change. The sliding wear test isperformed on a pin-on-disc apparatus using steel disc and brass pin. The investigation resultsshow that wear particle accumulation presents a strong bi-fractal behavior. Also, the fractal dimen-sion varies in correspondence to the wear status change. A new fractal index characterizing thewear particle accumulation is put forward. The wear tests of brass pin demonstrate that the fractalindex is effective in describing the wear status change.展开更多
Al-Sn alloys were produced by the induction melting method with different Bi additions. Microstructure shows grains 130 μm average size. Fracture toughness and hardness tests have shown that ternary alloying elements...Al-Sn alloys were produced by the induction melting method with different Bi additions. Microstructure shows grains 130 μm average size. Fracture toughness and hardness tests have shown that ternary alloying elements present significantly affected the samples with Bi alloying. Plastic deformation was evaluated by using the forging test;the results have shown that the addition of 3.5 at.% Bi increased the value at least twice as compared with unalloyed sample. Wear test indicated that bismuth slightly affected the tribological behavior. It was found that a concentration of 3.0 at.% Bi, considerably enhances the alloys performance.展开更多
文摘A significant fraction of the non-exhaust particulate matter emissions from vehicular traffic comprises fine particles from the wear debris of brake pads and discs.Recent studies have shown that these emissions can be consistently reduced by using wear resistant disc coatings.This study thoroughly analyses the debris produced by a low-met brake pad,which is dyno-bench tested against both cast iron and WC-CoCr-coated brake discs.To achieve this,particles in the size range of 2.5|im to 30 nm were collected and characterized.The results showed a consistent reduction in the particle emission as well as in the concentration of iron oxides,which are mainly released from the disc tribo-oxidation in the coated disc.Furthermore,a few tungsten carbides,released from the coating,were also observed in the wear fragments.The results of this study can be useful for improving the protective coating and consequently help in reducing particulate matter emission further.
文摘The topography and distribution of wear particles produced in the wear process containmuch information about the wear status. Fractal geometry is applied in this paper to describe thewear particle accumulation in order to characterize the wear status change. The sliding wear test isperformed on a pin-on-disc apparatus using steel disc and brass pin. The investigation resultsshow that wear particle accumulation presents a strong bi-fractal behavior. Also, the fractal dimen-sion varies in correspondence to the wear status change. A new fractal index characterizing thewear particle accumulation is put forward. The wear tests of brass pin demonstrate that the fractalindex is effective in describing the wear status change.
文摘Al-Sn alloys were produced by the induction melting method with different Bi additions. Microstructure shows grains 130 μm average size. Fracture toughness and hardness tests have shown that ternary alloying elements present significantly affected the samples with Bi alloying. Plastic deformation was evaluated by using the forging test;the results have shown that the addition of 3.5 at.% Bi increased the value at least twice as compared with unalloyed sample. Wear test indicated that bismuth slightly affected the tribological behavior. It was found that a concentration of 3.0 at.% Bi, considerably enhances the alloys performance.
