Direct answer: “stainless steel wire” is a product family, not one interchangeable material. Buyers must define grade, wire condition, diameter, tolerance, surface, mechanical properties and the forming or service requirement.
Spring performance depends on grade, cold-work condition, diameter, tensile range, surface quality, coiling behavior and stress-relief route. A high tensile value alone does not confirm fatigue performance or forming suitability.
Cold-heading wire needs controlled surface condition, ductility and processing history so it can withstand upsetting and forming. State the finished fastener, reduction sequence and applicable material specification.
Mesh and braided products may prioritize diameter consistency, surface cleanliness, spool behavior and corrosion resistance. Welding consumables are governed by separate classifications and should not be selected as ordinary stainless wire.
304-type wire is widely used for general corrosion resistance, while 316-type wire may be considered where molybdenum improves resistance in some chloride-bearing environments. Higher alloy or duplex grades may be required for more severe service. Final selection depends on temperature, chemicals, stress, crevices and cleaning practice.
Cold drawing increases strength and changes ductility, residual stress and magnetic response. Mechanical-property limits normally vary with diameter and product specification. Put the required tensile range, elongation or forming test on the purchase order instead of asking for “hard wire” without a measurable acceptance criterion.