GlossaryKind of term: Manufacturing term1.4301 (304)
What is 1.4301 (304)?
1.4301 (X5CrNi18-10) is an austenitic chromium-nickel stainless steel without molybdenum, close to 304 and one of the most widely used stainless grades.
Chromium sits at about 18 % and nickel between 8 and 10.5 %; 304 is the comparable grade in US standards. It is used for enclosures, frames, kitchen and food equipment and pipework parts. Annealed, it is barely magnetic, and heat treatment will not harden it. Without molybdenum it resists chlorides less well than 1.4404.
What does the standard say about 1.4301 (304)?
The grade and its composition are listed in EN 10088-1, the delivery conditions per product form in EN 10088-2 and EN 10088-3. The US grade 304 (UNS S30400) is covered by ASTM standards per product form; its limits are close to those of 1.4301 but not the same. For welded construction in thicker sections there is 1.4307 (X2CrNi18-9), the low-carbon variant that corresponds to 304L.
How does 1.4301 (304) behave in the shop?
1.4301 machines better than 1.4404 but worse than carbon steel or free-cutting steel. It work-hardens under the cutting edge: a blunt insert or a tool that dwells in the cut hardens the layer beneath, and the next pass then runs through hardened material. That costs tool life and can break a tap. Sharp edges, adequate feed and coolant limit that. After cold working or heavy machining it can become slightly magnetic as part of the austenite transforms; that alone does not point to the wrong grade.
What is 1.4301 (304) often confused with?
1.4301 is not 1.4305, which contains sulphur for better chip breaking and is therefore less corrosion resistant and less suitable for welding. Nor is it 1.4307, which has less carbon and is intended for welded work. If the drawing says only stainless, ask the customer which grade is meant.
Frequently asked questions
What kind of material is 1.4301?
An austenitic stainless steel with chromium and nickel and no molybdenum, comparable to 304. It is the usual grade for enclosures, frames and food equipment, welds well and cannot be hardened by heat treatment.
Why is 304 harder to machine than carbon steel?
Because it work-hardens under the cutting edge and the chip breaks poorly. An edge that rubs or dwells hardens the material beneath it. Sharp inserts, a feed that is not too light and enough coolant counter it.
Is 1.4301 stainless magnetic after machining?
Barely, when annealed. After cold working or heavy machining it can become slightly magnetic as part of the austenite transforms to martensite. That says little about the grade; the certificate or a material analysis does.