The Influence of Heat-treating Process on the Microstructure and Wear Resistance of HMn59-2-1-0.5 Used in Car Synchro Converter Ring

The microstructure and wear resistance of car synchro converter ring with directly cooling and aging after quenching in 720℃ are studied. The result shows after the car synchro converter is directly cooled by air, wind, ash and sand or aged between 150 and 200℃ for an hour, the percentage of α is less than 5% and the hardness is in the range of (168±8)HB which can satisfy the demand on properties of car synchro converter. The wear resistance of aged at 200℃ for an hour is better than that of cooled by air, but the process cooled by air is simpler and cheaper and the wear resistance is equal to that of car synchro converter imported.