FUNCTIONAL COIN EXCELLENT IN DISCRIMINATION CHARACTERISTIC AND HAVING FRAUD PREVENTING FUNCTION, AUSTENITIC STAINLESS STEEL SHEET USED THEREFOR, AND METHOD FOR MANUFACTURING THE FUNCTIONAL COIN

摘要

PROBLEM TO BE SOLVED: To provide an austenitic stainless steel sheet for a coin which has excellent discrimination characteristics and a fraud preventing function and is used for a game machine and also to provide the functional coin. SOLUTION: The functional coin having excellent discrimination characteristics and a fraud preventing function is composed of an austenitic stainless steel sheet having a ferromagnetic-material part and a nonmagnetic part. This austenitic stainless steel sheet is provided with a composition by which a partially ring-shaped ferromagnetic-material part can be formed by the application of working strain by regulating the respective contents of components in such a way that Md30 represented by equation (A), Md30(°C)=551-462(C+N)-9.2Si-8.1Mn-13.7Cr-29(Ni+Cu)-18.5Mo ranges from 0°C to 60°C. The working strain is applied by means of press working. A hollow lid has a composition by which stable nonmagnetism can be attained after press working by regulating the respective contents of components in such a way that the Md(30) represented by the equation (A) ranges from -200°C to -20°C. COPYRIGHT: (C)2007,JPO&INPIT