| 1. |
- Jansson, Anders, et al.
(författare)
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Ultrafine Particle Formation from Wear
- 2010
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Ingår i: The International Journal of Ventilation. - : Informa UK Limited. - 1473-3315 .- 2044-4044. ; 9:1, s. 83-88
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Tidskriftsartikel (refereegranskat)abstract
- Much attention is given to the consequences of airborne particles on human health and well-being. Wear is one source of airborne particles and contributions in the urban environments from wheel-to-rail contacts and disc brakes cannot be neglected. Traditionally, mechanical wear has been associated with the generation of particles of diameters of some microns. However, the research described has found ultrafine particle generation from wear processes. Particle generation from wear was measured under controlled laboratory conditions. The wear was created through sliding contact in a tribometer (type "pin-on-disc") with different materials and with different sliding velocities and pressures, to represent rail traffic and automobile disc braking. Particle concentrations and size distributions in the air were determined for particle diameters from 10 nm up to more than 10 mu m. For most materials and conditions three particle size modes were found: one at 50-100 nm, one at a few hundred nm and one at a few mu m particle diameter.
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| 2. |
- Jansson, Anders, 1947-, et al.
(författare)
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Ultrafine particle formation from wear
- 2009
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Ingår i: Proceedings of Ventilation 2009, the 9th International Conference on Industrial Ventilation.
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Konferensbidrag (refereegranskat)abstract
- Much attention is given to the consequences of airborne particles on human health and well-being. Wear is one source of airborne particles and contributions in urban environments from wheel-to-rail contacts and disc brakes cannot be neglected. Traditionally mechanical wear has been associated with the generation of particles of diameters of some μm. However, we have also found ultrafine particle generation from wear processes. Particle generation from wear was measured under controlled laboratory conditions. The wear was created through sliding contact in a tribometer (type "pin-on-disc") with different materials and with different sliding velocities and pressures, to represent rail traffic and automobile disc braking. Particle concentrations and size distributions in the air were determined for particle diameters from 10 nm up to more than 10 μm. For most materials and conditions three particle size modes were found: one at 50-100 nm, one at a few hundred nm and one at a few μm particle diameter.
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| 3. |
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| 4. |
- Söderberg, Anders, et al.
(författare)
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On Airborne Wear Particles Emissions ofCommercial Disc Brake Materials– A Pin on Disc Simulation
- 2008
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- A novel test method was used to study the concentration and size distribution of airborne wear particles from disc brake materials. A pin-on-disc tribometer equipped with particle counting instruments was used as test equipment. Four different nonasbestoses-organic (NAO) linings for the U.S. market and four different low metallic linings for the EU market were tested against material from gray cast iron rotors. The result indicates that the low metallic linings are more aggressive to the rotor material then the NAO linings, resulting in higher amount of wear and concentrations of airborne wear particles. But, although there are variations in the measured particle concentrations, similar size distributions were obtained regardless of lining material.
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| 5. |
- Wahlström, Jens, et al.
(författare)
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A pin-on-disc simulation of airborne wear particles from disc brakes
- 2010
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Ingår i: Wear. - : Elsevier. - 0043-1648 .- 1873-2577. ; 268:5-6, s. 763-769
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Tidskriftsartikel (refereegranskat)abstract
- A novel test method was used to study the concentration and size distribution of airborne wearparticles from disc brake materials. A pin-on-disc tribometer equipped with particle countinginstruments was used as test equipment. Material from four different non-asbestos organic(NAO) pads and four different low metallic (LM) pads were tested against material from greycast iron rotors. The results indicate that the low metallic pads cause more wear to the rotormaterial than the NAO pads, resulting in higher concentrations of airborne wear particles.Although there are differences in the measured particle concentrations, similar size distributionswere obtained. Independent of pad material, the characteristic particle number distributions ofairborne brake wear particles have maxima around 100, 280, 350, and 550 nm.
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| 6. |
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| 7. |
- Wahlström, Jens, et al.
(författare)
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Airborne Wear Particles Emissions fromCommercial Disc Brake Materials– Passenger Car Field Test
- 2008
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Most modern passenger cars have disc brakes on the front wheels, which unlike drum brakes are not sealed off to the ambient air. During braking, there is wear to both the rotor and the pads. This wear process generates particles, which may become airborne. In field tests it is difficult to distinguish these particles from others in the surrounding environment. It may be preferable to use laboratory test stands where the cleanness of the surrounding air can be controlled. The validity of these test stands has to be verified by comparison with field tests and therefore a test series has been conducted. These tests were performed in Stockholm, Sweden, in urban traffic. Low metallic type brake pads and gray cast iron rotors were tested. The results indicate that this test methodology can be used to study the number and mass concentrations as well as size distributions of particles generated from car disc brakes. Overall, the measured mean particle number and mass diameters of the airborne particles were 0.39 μm and 1.5 μm, respectively.
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