Yantai HuiLi Auto Parts Co., Ltd. 
"HuiLi Brakes" produce the largest range of brake drum and brake discs in the world.
With over 3000 part numbers for every type of moving vehicle. The brake discs or brake rotors are made in the china.
Our product range includes brake discs or brake rotors for cars, trucks and SUV, brake rotors (brake discs) for every rolling vehicle on the planet.
Properties desired for brake rotors and drums
Design was follow OE specifications (dimensions and configuration).
Rotor was have a smooth non-directional surface finish
Rotors and drums was have engraved on them this information; brand , part number , minimum thickness, date of manufacturing (YYMMDD) and Made in PRC.
Brake rotors and drums was made of Gray cast iron SAE Grade G9 (old G2500) or G10 (old G3000) according to SAE J431 and should comply with these specifications;
1.- Chemical composition;
Element        Content (%)
Carbon;        3,00 - 3,70
Silicon;    1,30 - 2,80
Manganese;    0,9 maximum
Phosphorus;    0,20 maximum
Sulfur;        0,15 maximum
2.- Microstructure. 
2.1.- Graphite. At least 80% has to be type A. The rest could be types B, D and E. Type C is not allowed.
2.2.- Matrix structure;  It should be lamellar pearlite with up to 5% of carbon particles uniformly distributed. Ferrite should not exceed 15%.
2.3.- Hardness; It should be in Brinnel range from 147 to 269.
2.4.- Minimum tensile strength;  Minimum of 120MPa (considering test results made according to ASTM A438-62 with test sample type B).
2.5.- Minimum flexion strength; It should resist a 780daN longitudinal force with a minimum flexion of 3.6mm before breaking (considering test results made according to ASTM A438-62).
3.- Other specifications.
3.1.- Friction surface standard arithmetic deviation should be  less than 6.3μm (considering test results made according to ASTM A438-62).
3.2.- Run-out. It should be less than 0.1mm.
3.3.- Dynamic and static balancing. It should be below 120 x 10-3 N?m for automobiles and below 353 x 10-3 N?m for light trucks.