Method of manufacturing brake disc of heterogeneous materials and brake disc of heterogeneous materials manufactured using the same

Abstract

A method of manufacturing a brake disc of heterogeneous materials, may include a disc device and a hub device formed in a cast-bonding manner using different materials, includes performing a first casting for casting the disc device using a grey cast-iron material, performing a preparation step by placing the disc device in a casting mold as an insert, performing a second casting for preparing a brake disc cast product by injecting molten aluminum alloy into the casting mold and casting the hub device to be cast-bonded to the disc device, and performing an oxynitriding process for forming an oxynitride layer by smoothing a surface of the brake disc cast product and performing heat treatment in a gaseous atmosphere at a temperature ranging from 425 to 500° C.

1 - 7 . (canceled) 
     
     
         8 . A brake disc of heterogeneous materials, including a disc device including a grey cast-iron material and a hub device including an aluminum alloy material formed integrally with the disc device in a cast-bonding way, the brake disc including:
 an oxynitride layer formed on a surface of the disc device.   
     
     
         9 . The brake disc according to  claim 8 , wherein the oxynitride layer is formed on the surface of the disc device to a thickness ranging from 1 to 15 μm. 
     
     
         10 . The brake disc according to  claim 8 , wherein the hub device has a disc thickness variation of 7 μm or less and a run-out of 30 μm or less.