Nitrided maraging steel and method of manufacture thereof

摘要

A maraging steel is subjected to the aging to have a hardness of more than 500 Hv. A nitrided case is formed to have a depth that is about 20% to 50% to a ½ thickness of the maraging steel plate. An endless ring for a metal belt is constructed by the above maraging steel. According to methods of manufacturing the maraging steel and the endless ring, the nitrided case having the depth that is 20% to 50% of a distance from a plate surface to a center can be formed by executing an aging to have the hardness of more than 500 Hv, then executing a nitriding in the nitrogen atmosphere to which organic chloride is added.