Stainless Steel 434-1/4 Hard
Supply condition
AISI/SAE 434 · UNS S43400 · EN 1.4113, X6CrMo17-1 · JIS SUS434 · GB 10Cr17Mo
1/4 Hard = quarter hard
Light temper rolling for extra stiffness and flatness in panels that need only modest bending.
Values for the 1/4 Hard condition
Other 434 tempers and conditions
434 is listed in 4 conditions; see the grade overview at 434.
- Annealed
- 1/4 Hard
- Cold Drawn
- 1/2 Hard
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
AnnealedDefault mill annealed / cold rolled and annealed sheet, plate, bar | Default stocked condition: softest, maximum ductility for deep drawing, bending and roll forming. | 365 | 530 | 25 | 160 HB | — |
1/4 HardThis page Quarter hard | Light temper rolling for extra stiffness and flatness in panels that need only modest bending. | 500 | 620 | 14 | 13 HRC | — |
cold drawn / cold finished bar and wire | Bar and wire condition giving tighter tolerances, better surface and higher strength for machined fasteners and shafts. | 510 | 620 | 15 | 15 HRC | — |
Half hard | Higher-strength spring-like strip for clips and stiff brackets where only simple forming is required. | 620 | 725 | 8 | 22 HRC | — |
What is 434-1/4 Hard?
434-1/4 Hard is 434 supplied in the 1/4 Hard condition — light temper rolling for extra stiffness and flatness in panels that need only modest bending. 434-1/4 Hard has a yield strength of 500 MPa (72.5 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 77% of stainless steel grades. Elongation at break is 14% and the elastic modulus is 200 GPa (29 Msi). 434-1/4 Hard has a density of 7.7 g/cm³ (0.278 lb/in³), lighter than 83% of stainless steel grades. It melts at 1,425°C (2,597 °F). Annealed is the default condition FabDigit quotes; 1/4 Hard is available on request or by drawing note.
Advantages
- Easy to machine — 58/100, better than 97% of stainless steel grades
- Conducts heat well — 25 W/m·K (14.4 BTU/hr·ft·°F), better than 93% of stainless steel grades
- High strength — 500 MPa (72.5 ksi), better than 77% of stainless steel grades
- High electrical conductivity — 2.6 % IACS, better than 77% of stainless steel grades
Limitations
- Limited ductility — 14%, worse than 91% of stainless steel grades
- Difficult to weld — 50/100, worse than 77% of stainless steel grades
- Needs corrosion protection — 52/100, worse than 76% of stainless steel grades
434-1/4 Hard properties
Typical room-temperature values for 434-1/4 Hard; 17 are specific to this condition. Other listed values are 434 reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
434-1/4 Hard has a density of 7.7 g/cm³ (0.278 lb/in³), lighter than 83% of stainless steel grades. It melts at 1,425°C (2,597 °F).
Mechanical14
434-1/4 Hard has a yield strength of 500 MPa (72.5 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 77% of stainless steel grades. Elongation at break is 14% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
434-1/4 Hard is rated for continuous service to 760°C (1,400 °F). It conducts heat at 25 W/m·K (14.4 BTU/hr·ft·°F), better than 93% of stainless steel grades. Thermal expansion is 10.4 µm/m·K (5.78 µin/in·°F).
Electrical3
434-1/4 Hard conducts electricity at 2.6 % IACS, better than 77% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is fair (52/100), worse than 76% of stainless steel grades.
Sustainability4
Producing a kilogram of 434-1/4 Hard takes about 50 MJ of energy and emits 4 kg of CO₂ — less than 80% of stainless steel grades. Typical recycled content is 65%.
Manufacturability7
434-1/4 Hard's machinability is good (58/100, better than 97% of stainless steel grades); weldability fair (50/100); formability fair (50/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 434-1/4 Hard
Is 434 easy to machine?
Machines like 430 (≈55% of AISI 1212): use rigid setups, sharp positive-rake carbide, moderate speed with heavy positive feed and flood coolant to avoid work hardening and built-up edge.
Can 434 be welded?
Readily GTAW/GMAW/resistance welded, but keep heat input low and avoid preheat/interpass above ~200 °C; HAZ grain coarsening lowers toughness — use 316L or 430Nb-type filler and post-weld anneal (760–815 °C) where ductility matters.
Can 434 be formed, bent or molded?
Good cold formability in the annealed condition for deep drawing and roll forming; springback is lower than austenitics, but plan for possible ridging/roping on drawn faces and avoid tight bends on transverse-oriented cold-worked strip.
What surface finishes work on 434?
Takes a bright mechanical or electropolished finish and is commonly supplied BA for trim; passivate after machining/welding, and use PVD or clear coat rather than anodizing.
434 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 |
|---|---|---|
| C | ≤ 0.12 | 0.05 |
| Si | ≤ 1 | 0.5 |
| Mn | ≤ 1 | 0.5 |
| P | ≤ 0.04 | 0.03 |
| S | ≤ 0.03 | 0.01 |
| Cr | 16 – 18 | 17 |
| Mo | 0.75 – 1.25 | 1 |
| Fe | balance | — |
434-1/4 Hard — frequently asked
What is 434-1/4 Hard used for?
434-1/4 Hard is typically used for automotive exterior trim and bright mouldings, solar water heater panels and tanks, appliance panels and fascias, kitchen and catering equipment panels, roofing and cladding sheet in mild chloride exposure and automotive wheel covers and mirror housings. In short: molybdenum-bearing ferritic stainless.
What is the yield strength of 434-1/4 Hard?
434-1/4 Hard has a typical yield strength of 500 MPa (72.5 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 77% of stainless steel grades. Strength varies by condition: see the 4 listed tempers.
Is 434-1/4 Hard easy to machine?
Reasonably — machinability is rated good (58/100, better than 97% of stainless steel grades). Machines like 430 (≈55% of AISI 1212): use rigid setups, sharp positive-rake carbide, moderate speed with heavy positive feed and flood coolant to avoid work hardening and built-up edge.
Can 434-1/4 Hard be welded?
With care — weldability is rated fair (50/100). Readily GTAW/GMAW/resistance welded, but keep heat input low and avoid preheat/interpass above ~200 °C; HAZ grain coarsening lowers toughness — use 316L or 430Nb-type filler and post-weld anneal (760–815 °C) where ductility matters.
What surface finishes work on 434-1/4 Hard?
Takes a bright mechanical or electropolished finish and is commonly supplied BA for trim; passivate after machining/welding, and use PVD or clear coat rather than anodizing.
Can 434-1/4 Hard be formed, bent or molded?
Good cold formability in the annealed condition for deep drawing and roll forming; springback is lower than austenitics, but plan for possible ridging/roping on drawn faces and avoid tight bends on transverse-oriented cold-worked strip.
What is the maximum service temperature of 434-1/4 Hard?
434-1/4 Hard is rated for continuous use to about 760°C (1,400 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Can FabDigit make parts in 434-1/4 Hard?
Yes — 434-1/4 Hard 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 A240/A240M — Chromium and Chromium-Nickel Stainless Steel Plate, Sheet, and Strip — ASTM International (2023)
- ASTM A176 — Stainless and Heat-Resisting Chromium Steel Plate, Sheet, and Strip — ASTM International (2022)
- ASM Specialty Handbook: Stainless Steels — ASM International (1994)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- Ferritic stainless steel grade datasheets (17Cr-1Mo / 434) — Outokumpu / AK Steel (Cleveland-Cliffs) (2021)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.