Diphasic stainless steel

Abstract

The invention discloses a biphase stainless steel, which is especially suitable for the steel used for coinage. The biphase stainless steel comprises the chemical components by weight percentage (wt percent) as follows: C and N are less than or equal to 0.12 percent, Si is less than or equals to 1.0 percent, Mn is less than or equals to 6.0 percent, P is less than or equals to 0.04 percent, S is less than or equals to 0.01 percent, Ni is 3.0 to 7.0 percent, Cr is 20.0 to 28.0 percent, Mo is 0 to 2.0 percent, W is 0 to 2.0 percent, binary master alloy that is Ag-Cu is 0.10 to 1.0 percent, and the other weight percentage is composed of Fe and ineluctable impurities, wherein, the ratio (that is Creq/Nieq) between Cr valent weight and Ni valent weight ranges from 3.0 to 3.8. The volume percentage of the biphase stainless steel in a cold-rolling annealed ferrite is 65 to 85 percent, and the saturation magnetic induction thereof is 0.7 to 1.0T. The biphase stainless steel has good heat formability, low hardness and good plasticity; the erosion resistance is better than the existing coinage stainless steel, and the anti-fake performance and the bacteria resistance performance are realized.

Description

technical field [0001] The invention relates to a duplex stainless steel, in particular to a coin-making duplex stainless steel with anti-counterfeiting and antibacterial properties. Background technique [0002] With the continuous development and progress of society, it is an international trend that metal coins are used as a supplement to banknotes to replace low-value banknotes, that is, coinage of secondary currency. The high-frequency circulation of low-denomination banknotes has at least the following disadvantages: ①Easily damaged and perishable, with a short circulation life; ②Easily dirty, and may carry bacteria and viruses; ③The cost of counting banknotes is huge (such as the banknote business of bus companies);④ Hinder the development of automatic coin collection business (such as unmanned ticket vending cars, vending machines, coin-operated phones, entertainment facilities, etc.). Coins overcome the shortcomings of the above banknotes, and should be welcomed an...

AI Technical Summary

Problems solved by technology

The high-frequency circulation of low-denomination banknotes has at least the following disadvantages: ①Easily damaged and perishable, with a short circulation life; ②Easily dirty and may carry bacteria and viruses; ③The cost of counting banknotes is huge (such as the zero banknote business of bus companies);④ Hinder the development of automatic coin collection business (such as unmanned ticket vending cars, vending machines, coin-operated phones, entertainment facilities, etc.)

Moreover, the stainless steel used for coinage does not have antibacterial properties.

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