Stainless Steel 302HQ
AISI/SAE 302HQ · UNS S30430
302HQ (UNS S30430 / XM-7) is an 18-8 austenitic stainless steel with 3–4 % copper added to cut the work-hardening rate for cold heading.
Values for the Cold Drawn condition
302HQ tempers and conditions
302HQ is supplied in 4 conditions, soft to hard. Cold Drawn is the default FabDigit quotes; the values on this page are for it.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
solution annealed cold-heading quality (CHQ) wire/rod | Choose for the most severe multi-station cold heading, deep recessed heads and thread rolling where maximum ductility is needed. | 230 | 520 | 55 | 140 HB | — |
Cold DrawnDefault light-to-moderate cold drawn wire/bar (as-drawn) | Default stock condition: cold-drawn coil/bar with higher strength and good surface, still headable for moderate upsets. | 400 | 620 | 28 | 185 HB | — |
Cold Worked 1/4-Hard | Use when a modest strength increase is wanted but partial upsetting or bending is still required. | 550 | 760 | 18 | 22 HRC | 2.4 % IACS |
Cold Worked 1/2-Hard | For rivets, springs-like parts and shafts needing strength; heading capability is largely lost. | 720 | 930 | 10 | 30 HRC | 2.4 % IACS |
Supply forms, finishes and certifications
Ways 302HQ is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
Cold Headed | Cold Headed / Thread Rolled | Surface finish |
What is 302HQ?
302HQ (UNS S30430 / XM-7) is an 18-8 austenitic stainless steel with 3–4 % copper added to cut the work-hardening rate for cold heading. The copper lets multi-station headers form deep-recess screws, bolts, rivets and self-tapping fasteners in one operation without cracking; it is supplied as annealed and cold-drawn wire, cold-headed blanks and CW 1/4H and 1/2H tempers. Corrosion resistance matches 304 and formability (score 88) is clearly better, but strength is lower, it cannot be hardened by heat treatment, and the copper makes welds hot-crack sensitive and pickling and passivation more demanding. Use 304 when weldability governs. 302HQ has a density of 7.9 g/cm³ (0.285 lb/in³), heavier than 68% of stainless steel grades. It melts at 1,398°C (2,548 °F). 302HQ has a yield strength of 400 MPa (58 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 57% of stainless steel grades. Elongation at break is 28% and the elastic modulus is 193 GPa (28 Msi).
What is 302HQ used for?
- Fasteners
- Screws
- Rivets
Advantages
- Forms and bends easily — 88/100, better than 97% of stainless steel grades
- Polishes to a fine finish — 80/100, better than 89% of stainless steel grades
302HQ properties
Typical room-temperature values for 302HQ-Cold Drawn; bars are the position among stainless steel grades.
Physical3
302HQ has a density of 7.9 g/cm³ (0.285 lb/in³), heavier than 68% of stainless steel grades. It melts at 1,398°C (2,548 °F).
Mechanical14
302HQ has a yield strength of 400 MPa (58 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 57% of stainless steel grades. Elongation at break is 28% and the elastic modulus is 193 GPa (28 Msi).
Thermal6
302HQ is rated for continuous service to 500°C (932 °F). It conducts heat at 16.2 W/m·K (9.36 BTU/hr·ft·°F), better than 64% of stainless steel grades. Thermal expansion is 17.3 µm/m·K (9.61 µin/in·°F).
Electrical3
302HQ conducts electricity at 2.4 % IACS, better than 67% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is good (63/100), better than 53% of stainless steel grades.
Sustainability4
Producing a kilogram of 302HQ takes about 53 MJ of energy and emits 4.9 kg of CO₂ — less than 67% of stainless steel grades. Typical recycled content is 60%.
Manufacturability7
302HQ's machinability is fair (42/100, better than 79% of stainless steel grades); weldability good (65/100); formability excellent (88/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the stainless steel family
Yield strength against density for every stainless steel grade FabDigit runs. 302HQ is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 302HQ
Is 302HQ easy to machine?
Gummy and work-hardening like 304 (≈45 % of AISI 1212): use positive rake carbide, rigid setups, heavy flood coolant and avoid dwelling; not a free-machining grade.
Can 302HQ be welded?
Weldable by GTAW/resistance methods with 308L or 309L filler, but the Cu-bearing, near-zero-ferrite weld metal is hot-crack sensitive — keep heat input low and avoid autogenous welds on restrained joints.
Can 302HQ be formed, bent or molded?
Best-in-class cold headability among 18-8 grades: multi-station heading, deep recess punching and thread rolling in the annealed condition with chlorinated or synthetic heading lube.
Manufacturability
The process limits FabDigit applies to 302HQ. Every 302HQ part is priced by an engineer; design inside these and the quote comes back without a redesign loop.
Sheet metal
| Formability | Excellent88 / 100 |
|---|---|
| Weldability | Excellent65 / 100 |
| Bendable | Yes |
302HQ chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| C0.08 max in some wire specs | ≤ 0.1 | 0.06 |
| Mn | ≤ 2 | 1.2 |
| Si | ≤ 1 | 0.5 |
| P | ≤ 0.05 | |
| S | ≤ 0.03 | |
| Cr | 17 – 19 | 18 |
| Ni | 8 – 10 | 9.2 |
| Cukey addition: lowers work-hardening rate for cold heading | 3 – 4 | 3.4 |
| Fe | balance |
What surface finishes work on 302HQ?
Passivate per ASTM A967 (nitric or citric) after forming; electropolish or barrel-polish for bright fasteners; not anodizable and Cu smut must be pickled off before plating.
Surface treatments FabDigit runs on stainless steel parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Plating
Organic Coating
Black / Phosphate
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Stainless Steel 302HQ in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- S30430
How much does 302HQ cost?
302HQ is a premium-cost stainless steel ($$$), cheaper than about 58% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
302HQ — frequently asked
What is 302HQ used for?
302HQ is typically used for fasteners, screws and rivets. In short: cold-heading fastener stainless.
What is the yield strength of 302HQ?
302HQ has a typical yield strength of 400 MPa (58 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 57% of stainless steel grades. Strength varies by condition: see the 4 listed tempers.
Is 302HQ easy to machine?
Not especially — machinability is rated fair (42/100, better than 79% of stainless steel grades). Gummy and work-hardening like 304 (≈45 % of AISI 1212): use positive rake carbide, rigid setups, heavy flood coolant and avoid dwelling; not a free-machining grade.
Can 302HQ be welded?
Yes — weldability is rated good (65/100). Weldable by GTAW/resistance methods with 308L or 309L filler, but the Cu-bearing, near-zero-ferrite weld metal is hot-crack sensitive — keep heat input low and avoid autogenous welds on restrained joints.
What surface finishes work on 302HQ?
Passivate per ASTM A967 (nitric or citric) after forming; electropolish or barrel-polish for bright fasteners; not anodizable and Cu smut must be pickled off before plating.
Can 302HQ be formed, bent or molded?
Best-in-class cold headability among 18-8 grades: multi-station heading, deep recess punching and thread rolling in the annealed condition with chlorinated or synthetic heading lube.
What is the maximum service temperature of 302HQ?
302HQ is rated for continuous use to about 500°C (932 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does 302HQ cost?
302HQ is a premium-cost stainless steel ($$$), cheaper than about 58% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Can FabDigit make parts in 302HQ?
Yes — 302HQ is available for sheet metal; every part is priced by an engineer rather than instantly. Upload a STEP file to get a price and a DFM check.
Sources
- ASTM A493 — Stainless Steel Wire and Wire Rods for Cold Heading and Cold Forging — ASTM International (2023)
- ASTM A276 / A493 chemistry for UNS S30430 (XM-7) — ASTM International (2023)
- SAE J405 — Chemical Compositions of SAE Wrought Stainless Steels — SAE International (2013)
- ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- Cold-heading quality stainless wire grade 302HQ / S30430 data sheet — stainless wire producers (e.g. Sandvik / Suzuki Garphyttan class data) (2022)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.