430 vs 304 Stainless Steel
Side-by-side comparison · Composition · Properties · Selection guide
430 is a 17% chromium ferritic stainless with no nickel; 304 is the 18/8 austenitic benchmark. 430 costs less and its price barely moves with the nickel market, it is magnetic, and it resists mild indoor corrosion well. 304 forms deeper, welds better, tolerates weather and chemicals, and stays tough at low temperature.
Full datasheets:430 Stainless Steel·304 Stainless Steel
At a Glance
| 430 | 304 | |
|---|---|---|
| Type | Ferritic | Austenitic |
| UNS | S43000 | S30400 |
| Standard | ASTM A240/A240M | ASTM A240/A240M |
| Density | 7.7 g/cm³ | 7.93 g/cm³ |
Corrosion Resistance and Service Limits
430
- Ferritic grades resist chloride stress-corrosion cracking better than common austenitic grades, while pitting resistance still depends on chromium, molybdenum and exposure.
- Weld condition, section thickness, crevices, deposits and surface contamination can control service performance; validate the actual fabrication and environment.
304
- General corrosion resistance comes from the chromium-rich passive film; nickel, molybdenum, nitrogen and copper change performance by grade.
- Check chlorides, temperature, crevices, deposits, process chemistry and cleaning conditions. A grade designation alone is not a service-life guarantee.
Fabrication and Heat Treatment
| Operation | 430 | 304 |
|---|---|---|
| Welding | Control heat input, interpass temperature and joint design to limit grain growth and loss of toughness; stabilized grades improve but do not remove these controls. | Generally weldable with a qualified procedure and matching or over-alloyed filler where required; remove heat tint when corrosion service demands it. |
| Forming | Formability is useful in sheet gauges but lower than common austenitic grades, especially in heavy sections and severe draws. | Good ductility is typical, but rapid work hardening increases forming load and springback; bend radius and intermediate annealing depend on grade and reduction. |
| Machining | Machining is generally straightforward with rigid tooling; avoid smearing, overheating and iron contamination of finished surfaces. | Use rigid tooling, positive feeds and controlled heat because the material work-hardens; free-machining grades require separate corrosion and welding review. |
| Heat treatment | Ferritic grades are not hardened by heat treatment. Annealing can restore ductility, but the temperature and cooling route must follow the product specification. | Solution annealing and rapid cooling restore the intended condition where applicable. Austenitic grades are not hardened by conventional quench-and-temper treatment. |
Chemical Composition (wt%)
| Element | 430 | 304 |
|---|---|---|
| C | ≤0.12 | ≤0.08 |
| Mn | ≤1.00 | ≤2.00 |
| Si | ≤1.00 | ≤0.75 |
| Cr | 16.0–18.0 | 17.5–19.5 |
| P | ≤0.040 | ≤0.045 |
| S | ≤0.030 | ≤0.030 |
| Ni | — | 8.0–10.5 |
| N | — | ≤0.10 |
Mechanical Properties
| Property | 430 | 304 |
|---|---|---|
| Tensile strength | ≥450 MPa (65 ksi) | ≥515 MPa (75 ksi) |
| Yield strength (0.2%) | ≥205 MPa (30 ksi) | ≥205 MPa (30 ksi) |
| Elongation (50 mm) | ≥22% | ≥40% |
| Hardness | — | ≤201 HBW |
Which One Should You Choose?
Choose 430 for:
- Appliance panels, range hoods and interior trim
- Magnetic applications (induction cookware bases)
- Cost-stable contracts insulated from nickel volatility
- Mildly corrosive, dry indoor environments
Choose 304 for:
- Outdoor or coastal exposure
- Deep-drawn sinks, pots and complex pressings
- Welded assemblies without post-weld annealing
- Sub-zero service where ferritics turn brittle
Our verdict
For flat or simply bent indoor panels, 430 delivers stainless appearance at a clearly lower and steadier price. Move to 304 when the part is welded, deeply formed, chilled or exposed to weather. If you like 430 economics but must weld, the stabilized ferritic 439 bridges the gap.
Cost and Availability
Compare the current stock position, mill route, minimum production quantity, processing yield, testing and delivered cost for 430 and 304 at quotation time. A fixed price ratio would be misleading because product form, size, condition and market timing can change the commercial result.
Do Not Substitute Without Review
Do not replace 430 with 304, or the reverse, from the grade name alone. Recheck chemistry, mechanical-property condition, product standard, dimensions, corrosion environment, welding procedure and project approval before substitution.
430 & 304 Products We Export
430 Stainless Steel Coil
Ferritic 430 stainless steel coil in BA and 2B finish, in quotation-confirmed dimensions, slit to width — nickel-free pricing for appliance panels, trim and kitchen counters.
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304 Stainless Steel Sheet
304/304L stainless steel sheet in 2B, BA, No.4 and mirror finish, in quotation-confirmed dimensions, cut to size, with ordered documentation.
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304 Stainless Steel Welded Pipe
304 welded stainless steel pipe and tube to ASTM A312, A249 and A554 — industrial, sanitary and polished decorative, round, square and rectangular sections.
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304 Stainless Steel Round Bar
304/304L stainless steel round bar, in quotation-confirmed dimensions, bright drawn h9/h11 or peeled, cut to length — machining stock with full heat traceability.
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Frequently Asked Questions
Is 430 real stainless steel if a magnet sticks to it?
Yes. Magnetism only reflects the ferritic crystal structure, not quality. 430 contains 16–18% chromium — genuine stainless — while austenitic 304 happens to be non-magnetic. The magnet test identifies the family, not the grade's honesty.
Why is 430 so much cheaper than 304?
No nickel. Nickel typically represents the largest and most volatile share of austenitic stainless cost; ferritic 430 avoids it entirely, so its price tracks chromium and steel scrap instead.
Can 430 replace 304 in a welded product?
Only after engineering review. 430 has different weld ductility, corrosion behavior, thermal expansion and forming response, so a price-driven substitution can change fabrication and service life.
RFQ
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Technical content updated: 2026-07-29
Organizational author: Tsingshan (Shandong) Iron & Steel Co., Ltd..Review method, status and limitations.