Grade quotation brief
430 vs 304 Stainless Steel
Quote 430 when magnetic, controlled indoor and moderately formed sheet duty is already approved. Quote 304 when more severe forming, welded assemblies, low-temperature duty or broader environmental exposure controls the design. Confirm grade, product condition, joint design, finish and end-use approval before any substitution.
Quote 430 for controlled indoor, magnetic or moderately formed sheet after surface, joining and exposure are defined. Quote 304 when the component needs austenitic forming, low-temperature toughness or a different corrosion margin. A welded ferritic route such as 439 is a separate quote, not an informal swap.
Unsure whether 430 or 304 matches the operating temperature and chemistry? Send the service conditions with the RFQ. We quote the approved designation, product form and test plan.
Request a Quote
Illustrations identify the compared grade references; they are not photographs of the quoted material or proof of a mill heat.
Decision matrix
Key Differences
Full grade sheets:430 Stainless Steel/304 Stainless Steel
| Factor | 430 | 304 | Procurement decision |
|---|---|---|---|
| Metallurgical family | 430 is ferritic stainless steel with a chromium range and no specified nickel range in the displayed chemistry. | 304 is austenitic stainless steel with specified chromium and nickel ranges in the displayed chemistry. | Treat the grades as different engineering materials even when a polished sheet surface appears similar. |
| Magnet response | Annealed 430 is normally magnetic because of its ferritic structure, which can support induction or retention functions. | Annealed 304 is generally much less magnetic, although cold work can change its response and cannot identify the grade alone. | Specify any magnetic performance test separately; a handheld magnet is not a complete grade-verification method. |
| Forming and welding | 430 sheet can support moderate forming, but severe draws and welding require control of ductility, grain growth and section effects. | 304 commonly offers wider austenitic forming and welding routes, while work hardening, distortion and surface restoration still need review. | Provide the drawing and joint route; do not approve a material change from flat-sheet behavior alone. |
| Environmental duty | 430 is commonly screened for controlled indoor or mildly corrosive service with suitable finish, cleaning and drainage. | 304 is commonly evaluated for broader atmospheric and cleaned-equipment exposure, but chlorides can still cause localized attack. | Define salts, humidity, temperature, deposits and cleaning rather than ranking the grades with one corrosion label. |
Service and production route
Corrosion and Fabrication Boundaries
430 corrosion screening
- For this 430 vs 304 review, 430 forms a chromium-rich passive film suited to dry indoor atmospheres and many decorative appliance faces, but coastal exposure, persistent wetting and chloride cleaners can stain or pit sooner than on common austenitic grades such as 304.
- For this 430 vs 304 review, Ferritic grades generally resist chloride stress-corrosion cracking better than common austenitics, while pitting and crevice attack still depend on chromium level, surface finish, deposits and drainage — do not treat 430 as marine or chloride-primary service material.
- For this 430 vs 304 review, Against 201, corrosion ranking still depends on the actual humidity, salt and cleaning chemistry; against 304, annealed 430 is usually chosen for magnetic decorative indoor duty rather than as a corrosion upgrade. Validate fabrication and environment rather than relying on the grade name alone.
304 corrosion screening
- For this 430 vs 304 review, 304 relies on a chromium-rich passive film for general atmospheric, indoor and many process duties, but it is not automatically suitable for warm chloride, coastal salt deposits or persistent crevice-prone service — 316/316L or a higher alloy may be needed.
- For this 430 vs 304 review, Against lower-nickel 201, annealed 304 usually offers more corrosion margin in humidity, outdoor wetting and chemically cleaned food-contact duty; against ferritic 430 it remains the more formable, weldable austenitic default when magnetism and deep drawing matter.
- For this 430 vs 304 review, Review chlorides, temperature, pH, deposits, crevices, drainage, cleaning chemistry, weld heat tint and surface finish for the actual component. A grade designation alone is not a service-life guarantee.
| Operation | 430 | 304 |
|---|---|---|
| Welding | Control heat input, interpass temperature and joint design to limit grain growth and loss of toughness in the HAZ. Thin decorative sheet may be spot- or TIG-welded after trials; do not treat this page as a fabricated WPS — qualify the procedure for the ordered gauge and duty. | Generally weldable with a qualified austenitic procedure, matching or over-alloyed filler where required, controlled heat input and heat-tint removal when corrosion service demands it. For as-welded heavy sections, prefer 304L or dual-certified material meeting the low-carbon limit rather than assuming standard 304 HAZ behavior. |
| Forming | Annealed sheet and coil form adequately for bends and moderate stampings, but ductility and stretch formability are lower than common austenitic grades such as 304 or 201. Prove bend radius, draw severity and springback on the actual gauge. | Annealed 304 sheet and strip draw and bend well, but the alloy work-hardens during forming — tooling load, springback, bend direction, draw ratio and any intermediate anneal must be proven on the actual gauge and reduction route. |
| Machining | Machining is generally straightforward with rigid tooling; avoid smearing, overheating and iron contamination of finished decorative surfaces that will remain visible in BA or 2B. | Use rigid tooling, positive feeds and controlled cutting heat to avoid a work-hardened surface; qualify the route on the delivered condition. Free-machining sulfur grades (for example 303) require separate corrosion and welding review. |
| Heat treatment | Ferritic 430 is not hardened by conventional quench-and-temper treatment. Annealing can restore ductility after cold work, but temperature and cooling must follow the product specification — do not invent contractual heat-treat cycles here. | Solution annealing with rapid cooling restores the intended annealed austenitic condition after suitable cold work or fabrication where applicable. Conventional quench-and-temper treatment does not through-harden austenitic 304. |
Reference data
Composition and Mechanical Requirements
Values below come from each grade's displayed reference dataset. Product form, thickness, condition and contracted standard can change the applicable acceptance table.
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 | ≤183 HBW | ≤201 HBW |
Quotation workflow
Application Decisions
- For appliance panels and dry interior trim, evaluate 430 with the required finish, bend severity, edge exposure, cleaning method and cosmetic sample.
- For induction cookware construction, specify the magnetic layer and food-contact layers separately instead of treating 430 as a complete substitute for 304.
- For deep-drawn sinks or complex pressings, trial the actual coil and compare drawability, earing, springback, surface protection and annealed condition.
- For outdoor, welded or low-temperature assemblies, review 304 and any stabilized ferritic candidate against the complete design and environment.
Quote 430 when
- Appliance panels, range hoods and interior trim with an accepted 430 finish
- Magnetic applications such as induction cookware bases named as 430
- Indoor dry panels whose joining and exposure basis already names 430
- Mild indoor duty where magnetism or the ferritic route is a drawing requirement
Quote 304 when
- Outdoor or coastal exposure
- Deep-drawn sinks, pots and complex pressings
- Welded assemblies without post-weld annealing
- Sub-zero service where ferritic toughness must be reviewed
Hold point
Do Not Substitute Without Review
- Do not replace 304 with 430 from appearance or quoted price when the drawing, weld procedure, toughness or corrosion review names 304.
- Do not use magnetic response as proof of exact grade, heat chemistry, condition or end-use performance.
- Do not infer a fixed service life for either grade from indoor, outdoor, appliance or architectural labels.
- Do not assume stabilized ferritic grades such as 439 are interchangeable with 430 or 304 without separate standard and fabrication approval.
Specification boundary
Standards, Temperature and Approval
Product and project approval
ASTM A240/A240M can govern relevant 430 and 304 plate, sheet and strip, while mechanical tube, finished cookware and other components invoke additional standards and end-use criteria. The purchase-order edition, drawing, product specification, approved material list and buyer authority control acceptance.
Temperature boundary
No single temperature figure on this page approves 430 or 304 for service. Low-temperature toughness, oxidation, thermal cycling, design stress, weld condition and corrosion environment invoke different criteria; the governing code, test data and project engineer must define the acceptable range.
Commercial comparison
Cost and Availability Factors
Quote 430 and 304 on one RFQ with the same product form, dimensions, tests and documents. This page does not represent current stock, price or lead time.
Cost factors
- Current mill route, alloy inputs and availability for the selected grade, product form and condition.
- Drawing yield, forming trials, weld route, surface finish, protection and cosmetic sample approval.
- Dimensions, tolerances, magnetic acceptance, inspection document, traceability and supplementary tests.
- Quantity, packing, freight, Incoterm, delivery timing and consequences of a non-approved substitution.
Inputs for a like-for-like quotation
- Required grade and UNS designation, governing product standard, edition and substitution approval route.
- Product form, dimensions, tolerances, quantity, annealed or other condition, finish and critical face.
- Part drawing, draw depth, bend direction, weld or joining route and surface-restoration process.
- Indoor or outdoor exposure, humidity, salts, cleaning, temperature, drainage and appearance criteria.
- Magnetic acceptance if functional, MTC type, heat traceability, tests, destination and Incoterm.
Continue the specification
Related Grades, Standards and Applications
Grade references
Standards
Applications
430 Stainless Steel Coil
Ferritic 430 coil in BA, 2B and No.4. Common inquiry range 0.2–3.0 mm, 1000/1219 mm or slit from 20 mm, for appliance panels, trim and kitchen equipment.
View details →
304 Stainless Steel Sheet
304/304L ASTM A240 sheet in 2B, BA, No.4 and mirror. Common inquiry range 0.3–6.0 mm, 1000/1219/1500 mm widths, cut to size with quoted documents.
View details →
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.
View details →
304 Stainless Steel Round Bar
304/304L round bar in bright, peeled or hot-finished routes. Common inquiry range 3–300 mm diameter, 3 m / 6 m or cut-to-length, for pins, shafts and fittings.
View details →
Buyer questions
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.
Published by Tsingshan (Shandong) Iron & Steel Co., Ltd..Sources, update policy and technical limitations.
Quote request
Get a Stainless Steel Quote
Send the product, grade and quantity you already have. We will complete the specification and quote the supply route.