Fe is the basis.
According to TU 3-1544-90 the chemical composition is given for steel grade 08H18N7G10AM3-P. Calculated mass fractions of cerium and calcium are set by the technological instruction and their residual mass fraction in the metal is not determined by chemical analysis. Presence of residual tungsten and vanadium is not more than 0.20% of each. At the request of the consumer, the wire is made of steel with narrow limits of the mass fraction of nitrogen, nickel, manganese. Limits of mass fraction for these elements are indicated in the order. The difference between the lower and upper limits should be at least: for manganese - 1.5%; nickel - 0,6%; nitrogen - 0.10%. The limiting deviations of the mass fraction of elements from the norms of the table should not exceed: by carbon - + 0.01%; silicon - + 0.20%; manganese - ± 0.10%; nickel - ± 0,30%; molybdenum - -0.20%. At the request of the consumer, the wire is made of steel with an increased content of silicon by a floating analysis: (0.80-1.60)%. In this case the steel has the designation 08Х18Н7Г10АМ3С2-ПД