B, stainless steel is not easy to rust, can be used for the manufacture of medical equipment; so B is correct;
C, silicon-steel alloy of ferrosilicon, is an important soft magnetic alloy indispensable to the electric, electronic and military industries. It is an important soft magnetic alloy indispensable to electric power, electronics and military industry, so C is wrong;
D, tungsten steel belongs to the cemented carbide, commonly used in high-precision machining, high-precision cutting tool materials, so D is wrong;
Therefore, the choice of B.
Therefore, the choice of B.
B, tungsten steel is not easy to rust.