Abstract: Based upon RM Tong's thought of regarding fuzzy model as the set of fuzzy conditional proposition by converting the accurate value into a fuzzy one, the structure of a fuzzy system formed by alloy element adding amount and material characteristic norm is determined, and then the fuzzy model of the system is built. This new general method for studying the influence of alloy adding upon the material characteristics is presented in detail.

Key words: material characteristics, fuzzy model, alloy element