Stainless Steel S42030
UNS S42030
S42030 is a carbon-adjusted 420 martensitic stainless supplied annealed, hot-rolled annealed, cold-drawn, as cold-rolled strip, hardened, and in tempered conditions from QT-205 through QT-650.
Reference datasheet — S42030 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the A condition
S42030 tempers and conditions
S42030 is supplied in 8 conditions, soft to hard. A is the default FabDigit quotes; the values on this page are for it.
Compare all 8 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
ADefault Solution annealed | Standard stocking condition for bar, plate and forgings — soft, machinable, to be hardened after machining. | 380 | 690 | 22 | 210 HB | — |
Annealed and cold drawn bar | Cold-drawn bar for close tolerance and better surface finish on screw-machine parts. | 690 | 830 | 14 | 25 HRC | 3.1 % IACS |
Hardened and tempered at 650 °C | High-temper 'quenched and tempered structural' condition (~26–32 HRC) for shafts, bolts and forgings where ductility and machinability matter more than wear. | 690 | 900 | 18 | 29 HRC | — |
Hardened and tempered at 540 °C | Intermediate ~38–43 HRC condition for shafts and pump/valve components needing more toughness than blade tempers. | 1,030 | 1,280 | 13 | 40 HRC | — |
Hardened and tempered at 425 °C (800 °F) — embrittlement range, avoid… | Only used when a specific ~45–48 HRC level is required; toughness and corrosion resistance both drop in the 400–550 °C tempering range. | 1,330 | 1,550 | 10 | 47 HRC | 2.9 % IACS |
Hardened and tempered at 315 °C | Slightly tougher than 205 °C temper for shafts, valve parts and dies at ~48–52 HRC. | 1,400 | 1,650 | 9 | 50 HRC | — |
Hardened and tempered at 205 °C | Standard cutlery/blade and wear-part condition: near-peak hardness with usable toughness and best corrosion behaviour of the hardened states. | 1,480 | 1,750 | 8 | 52 HRC | — |
Hardened | Maximum hardness condition for cutting edges and wear surfaces where toughness demand is low. | 1,550 | 1,860 | 4 | 55 HRC | — |
Supply forms, finishes and certifications
Ways S42030 is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
CR-STRIP | CR | Supply form |
HRA | Hot rolled / forged and annealed bar & plate | Surface finish |
What is S42030?
S42030 is a carbon-adjusted 420 martensitic stainless supplied annealed, hot-rolled annealed, cold-drawn, as cold-rolled strip, hardened, and in tempered conditions from QT-205 through QT-650. It is specified for cutlery-grade blades, instruments and wear parts because it hardens to high strength, holds an edge and takes an excellent polish. Annealed values are about 380 MPa yield, 690 MPa tensile, 22% elongation and 210 HB (95 HRB), with service to 650 °C. Corrosion resistance is limited (score 38) and weldability is poor at this carbon level; S42010 (420 Mod) offers more hardness and corrosion resistance. S42030 has a density of 7.75 g/cm³ (0.28 lb/in³), lighter than 65% of stainless steel grades. It melts at 1,450°C (2,642 °F). S42030 has a yield strength of 380 MPa (55.1 ksi) and a tensile strength of 690 MPa (100 ksi) — stronger than 52% of stainless steel grades. Elongation at break is 22% and the elastic modulus is 200 GPa (29 Msi).
What is S42030 used for?
- Knife blades
- Surgical instruments
- Molds and dies
- Wear plates
Advantages
- High electrical conductivity — 3.1 % IACS, better than 99% of stainless steel grades
- Polishes to a fine finish — 85/100, better than 97% of stainless steel grades
- Conducts heat well — 24.9 W/m·K (14.4 BTU/hr·ft·°F), better than 87% of stainless steel grades
Limitations
- Needs corrosion protection — 38/100, worse than 95% of stainless steel grades
- Difficult to weld — 25/100, worse than 92% of stainless steel grades
- Limited ductility — 22%, worse than 75% of stainless steel grades
S42030 properties
Typical room-temperature values for S42030-A; bars are the position among stainless steel grades.
Physical3
S42030 has a density of 7.75 g/cm³ (0.28 lb/in³), lighter than 65% of stainless steel grades. It melts at 1,450°C (2,642 °F).
Mechanical15
S42030 has a yield strength of 380 MPa (55.1 ksi) and a tensile strength of 690 MPa (100 ksi) — stronger than 52% of stainless steel grades. Elongation at break is 22% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
S42030 is rated for continuous service to 650°C (1,202 °F). It conducts heat at 24.9 W/m·K (14.4 BTU/hr·ft·°F), better than 87% of stainless steel grades. Thermal expansion is 10.3 µm/m·K (5.72 µin/in·°F).
Electrical3
S42030 conducts electricity at 3.1 % IACS, better than 99% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is fair (38/100), worse than 95% of stainless steel grades.
Sustainability4
Producing a kilogram of S42030 takes about 48 MJ of energy and emits 4.3 kg of CO₂ — less than 85% of stainless steel grades. Typical recycled content is 50%.
Manufacturability6
S42030's machinability is fair (42/100, better than 79% of stainless steel grades); weldability poor (25/100); formability fair (38/100).
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. S42030 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with S42030
Is S42030 easy to machine?
Machine in the annealed condition with sharp, rigid, positive-rake carbide tooling, generous feed and flood coolant; above ~45 HRC switch to grinding, EDM or ceramic/CBN hard turning.
Can S42030 be welded?
Poor weldability due to high carbon — preheat 200–320 °C, use 410/420 or austenitic (309/312) filler, and temper immediately after welding to avoid quench cracking.
Can S42030 be formed, bent or molded?
Cold form only in the annealed condition and with generous bend radii; hot work 1100–1200 °C, stop above ~900 °C and cool slowly followed by a full anneal.
S42030 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 |
|---|---|---|
| Ccarbon-adjusted (high-carbon) 420 variant; exact limits per the governing ASTM A276/A959 or purchase spec | 0.28 – 0.4 | 0.33 |
| Si | ≤ 1 | 0.4 |
| Mn | ≤ 1 | 0.5 |
| P | ≤ 0.04 | |
| S | ≤ 0.03 | |
| Cr | 12 – 14 | 13 |
| Niresidual/optional addition in some mill practices | ≤ 0.5 | |
| Moresidual/optional addition in some mill practices | ≤ 0.5 | |
| Fe | balance |
What surface finishes work on S42030?
Takes an excellent mirror or satin polish; passivate in nitric or citric acid after machining/grinding, and avoid electroless/hard chrome hydrogen embrittlement without a post-plate bake.
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).
Passivation
Organic Coating
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Stainless Steel S42030 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- Similar grades
- 420S42000
How much does S42030 cost?
S42030 is a standard-cost stainless steel ($$), cheaper than about 71% 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.
S42030 — frequently asked
What is S42030 used for?
S42030 is typically used for knife blades, surgical instruments, molds and dies and wear plates. In short: classic hardenable blade steel; wide tempered range QT-205–QT-650; polishes to mirror finish.
What is the yield strength of S42030?
S42030 has a typical yield strength of 380 MPa (55.1 ksi) and a tensile strength of 690 MPa (100 ksi) — stronger than 52% of stainless steel grades. Strength varies by condition: see the 8 listed tempers.
Is S42030 easy to machine?
Not especially — machinability is rated fair (42/100, better than 79% of stainless steel grades). Machine in the annealed condition with sharp, rigid, positive-rake carbide tooling, generous feed and flood coolant; above ~45 HRC switch to grinding, EDM or ceramic/CBN hard turning.
Can S42030 be welded?
Not readily — weldability is rated poor (25/100). Poor weldability due to high carbon — preheat 200–320 °C, use 410/420 or austenitic (309/312) filler, and temper immediately after welding to avoid quench cracking.
What surface finishes work on S42030?
Takes an excellent mirror or satin polish; passivate in nitric or citric acid after machining/grinding, and avoid electroless/hard chrome hydrogen embrittlement without a post-plate bake.
Can S42030 be formed, bent or molded?
Cold form only in the annealed condition and with generous bend radii; hot work 1100–1200 °C, stop above ~900 °C and cool slowly followed by a full anneal.
What is the maximum service temperature of S42030?
S42030 is rated for continuous use to about 650°C (1,202 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between S42030-A and S42030-H?
A is the default condition — standard stocking condition for bar, plate and forgings — soft, machinable, to be hardened after machining. H: maximum hardness condition for cutting edges and wear surfaces where toughness demand is low. Yield strength is 380 MPa in A versus 1,550 MPa in H.
How much does S42030 cost?
S42030 is a standard-cost stainless steel ($$), cheaper than about 71% 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.
Sources
- ASTM A276/A276M — Stainless Steel Bars and Shapes — ASTM International (2023)
- ASTM A959 — Harmonized Standard Grade Compositions for Wrought Stainless Steels — ASTM International (2022)
- GB/T 1220 (4Cr13 / 3Cr13) — SAC (2007)
- ASM Specialty Handbook: Stainless Steels — ASM International (1994)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- Type 420 Stainless Steel Product Data Bulletin — AK Steel / Cleveland-Cliffs (2018)
- UNS S42000/S42030 martensitic stainless property records — SAE/ASTM Metals & Alloys in the Unified Numbering System (2019)
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.