Patent ID: 8585833
Filing Date: 2013-11-19
Classification: C21D,C23C,F16D

Abstract:
1. A method for nitrocarburizing brake rotors of a motor vehicle, comprising the steps of: casting a ferrous brake rotor having mutually opposed first and second rotor cheeks; providing a nitrocarburizing salt bath; providing an oxidizing salt bath; pre-heating the brake rotor to a first predetermined temperature; immersing the brake rotor into the nitrocarburizing salt bath, wherein the nitrocarburizing salt bath is at a second predetermined temperature, and wherein the brake rotor is placed into the nitrocarburizing salt bath such that all surfaces of the first and second rotor cheeks are in contact with the nitrocarburizing salt bath; removing the brake rotor from the nitrocarburizing salt bath after a first predetermined dwell time; immersing the brake rotor into the oxidizing salt bath, wherein the oxidizing salt bath is at a third predetermined temperature, and wherein the brake rotor is placed into the oxidizing salt bath such that all surfaces of the first and second rotor cheeks are in contact with the oxidizing salt bath; removing the brake rotor from the oxidizing salt bath after a second predetermined dwell time; and cooling the brake rotor to substantially room temperature; wherein said first predetermined temperature is preselected and provided for a predetermined third dwell time such that the brake rotor is free of moisture prior to said first step of immersing, and further wherein said first predetermined temperature heats the brake rotor to a temperature at least medial between room temperature and said second predetermined temperature.