284 is a low-nickel austenitic stainless steel in the same general family as 201 and 202: manganese takes on part of the role nickel plays in a standard 18-8 grade like 304, keeping material cost down while retaining an austenitic, non-magnetic microstructure. Its chemistry runs roughly 17% chromium, 7-10% manganese, and around 5% nickel — close enough to 202's composition that it behaves as a cousin grade within the same economy-austenitic category, intended for applications where full nickel content isn't required for the service environment.

284 does not have a widely published DIN/EN/JIS cross-reference in general steel standards literature — it appears to be a specialty or mill-specific designation within the low-nickel austenitic family rather than a number carried in every international standard. Treat it as a Cr-Mn-Ni austenitic with the composition below, and confirm exact standard equivalents against mill certification if a specific national standard cross-reference is required.

No widely published international standard cross-reference was found for this designation — confirm exact composition against mill certification for critical applications.

284 machines like the rest of the low-nickel Cr-Mn-Ni austenitic family it belongs to: non-heat-treatable, so all of its strength comes from cold work, and it work-hardens faster than 304 or 316 because of its manganese-heavy, lower-nickel chemistry. Any rubbing, dwelling, or light finishing pass at the cutting edge strains and hardens the surface it touches, and that hardened layer is noticeably tougher for the next pass to cut through.

The same discipline used across the 201/202/284 low-nickel family applies here: keep the tool sharp and cutting rather than rubbing, use feed rates high enough to get under any hardened skin from a previous pass, and avoid dwelling or light skimming cuts on a dulling edge. Sharp, positive-rake geometries limit the burnishing action that drives work hardening, and a stainless-specific insert grade and chipbreaker handle 284's long, stringy chip formation better than a general carbon-steel option.

Assumes a well-matched insert grade, rigid tool and workpiece clamping, good-quality raw material, short tool overhang.

Turning

Parting / Grooving

Milling

A sharper edge preparation than a standard 304 setup helps the tool shear rather than burnish the surface, limiting work hardening.