Our cold-rolled tempered stainless — Quarter Hard, Half Hard and Full Hard — is listed as 302 / 304 for the same reason our annealed material is: one piece of material, certified to both alloys at once.
A temper is not a different alloy. It is the same 302/304 chemistry that has been cold rolled after annealing to raise its strength. The more reduction, the harder the temper. Because we buy to an overlapping chemistry that sits inside both the 302 and 304 windows, the finished coil can be certified to the 302 temper specification and the 304 temper specification simultaneously.
Temper is proven by mechanical testing, not by chemistry. At each temper, the tensile and yield minimums are the same for both types — so a coil that passes the test satisfies whichever type your print calls out.
Temper Specifications & Strength Minimums
Note on 304 Full Hard: ASTM A666 covers the three-quarter hard and full hard tempers for Types 301 and 302 only — Type 304 is not listed in ASTM A666 for the Full Hard temper. 304 Full Hard is therefore certified to AMS 5913 rather than ASTM A666.
Chemical Requirements — Type 302 & 304 (weight %)
How to read the overlap column: where the two alloys disagree, the tighter limit wins — carbon to 304’s 0.08 maximum, chromium to the 18.0–19.0 band the two ranges share, and nickel to 302’s ceiling of 10.0. Temper does not change any of these values; cold rolling changes strength, not chemistry.
Notes: Values are specification limits, not a mill analysis — actual chemistry and tensile results appear on the certified mill test report supplied with your order. Minimum elongation requirements vary by type and by thickness and are not shown here; they are stated on the mill certificate. Some AMS editions permit silicon to 1.00 max; the ASTM A666 limit of 0.75 max is shown because it governs.
