Technical specification of Friction Material and relate d standard for Brake Pads
Generally in order to producing brake pad in accordance with defined Standards that issue from National Standard Organization and also the Standards defined from automotive manufacturer:
Brake pads are deviated to 4 main group regarding friction materials that used in producing them.
1- Metal Brake Pads: The main Material is composed of metal and metallic alloy.
2- Semi Metal Brake Pads: The main material is a mixture of metallic yarn and mineral and organic material.
3- Low metal Brake Pads: the Basic Material is composed of Low quantity of metallic yarn and metallic powder.
4- Organic Brake Pads: The main material is composed of non-metallic yarn (mineral and organic)
Nowadays Friction material of group1, 2 are applied fewer than group 3 and 4, because of erosion that occurred in Brake disk, low metal and organic material are applied more in favor .Friction material is composed of different kind of metallic and non-metallic material (mineral and organic) which are produced with different specific percentage of mixture and should have a specified characteristic after production process. This characteristic shall be confirmed and also affirmed by proposed items arise through National Standard Organization.
1- Brake pads hardness : according to JIS D 4421 Standard 40-80 (HRS)
2- Porosity : according to JIS D 4418 Standard 12%-18%
3- Compressibility : according to ISO 6310 Standard
room temperature ‹ 2%
room temperature ‹ 5%
4- Coefficient of heat expansion : according to ISO 6313 Max 1%
5- PH : according to JIS K 6911 10-13 6- Density : according to JIS D 4418 2.53-2.71 g/cm3
7- Coefficient friction : according to National Standard
ISIRI 586 0.35-0.45
SAE J 661 F-F
SAE J 866
7-1- The percentage of allowed deviation from friction coefficient in scale from
its average in first and second basic tests of should be Max ±20%
7-2- The percentage of allowed deviation of friction coefficient in scale from its
average in first and second thermic tests should be Max ±30%
7-3- The percentage of allowed deviation µ in scale from its average in first
and second retrieval tests should be Max ±20%
7-4- The maximum special erosion 4.56*10-6 g/N.m
8- Lack of harsh sound while braking in field tests
9- Shear strength according to National Standard ISIRI 2798
3 N/mm2 ≤ shear strength: room temperature
2.25 N/mm2 ≤ shear strength 300 C temperature
10-Usage of any kind of Asbestos material is forbidden
11- usage of Plumbed id forbidden