Stainless Steel 1.4305
EN 1.4305 · UNS S30300 · AISI/SAE 303 · JIS SUS303 · GB Y1Cr18Ni9
1.4305 (X8CrNiS18-9, S30300/303, SUS303) is the sulphur-added free-machining austenitic stainless, where 0.15–0.35 % S forms sulphide inclusions that break chips and cut tool wear.
Reference datasheet — 1.4305 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 +AT condition
1.4305 tempers and conditions
1.4305 is supplied in 5 conditions, soft to hard. +AT is the default FabDigit quotes; the values on this page are for it.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
+ATDefault Solution annealed | Standard stock condition for hot-rolled/peeled and centreless-ground bar; maximum corrosion resistance and ductility, softest chips. | 260 | 620 | 48 | 160 HB | — |
+AT, peeled / centreless-ground bright bar | Annealed bar turned/ground to close diameter tolerance — pick when the outside diameter is used as-supplied on CNC parts. | 265 | 620 | 45 | 165 HB | 2.4 % IACS |
Cold drawn, Rm ≥ 700 MPa | Light cold-drawn bar: the usual automatic-lathe stock — straight, bright, better chip control and higher strength than +AT. | 520 | 760 | 25 | 230 HB | — |
Cold drawn, Rm ≥ 800 MPa | Harder cold-drawn bar for shafts, pins and fasteners needing higher proof strength and the cleanest possible turned finish. | 640 | 860 | 16 | 26 HRC | — |
Cold drawn, Rm ≥ 900 MPa | Heavily drawn small-diameter bar/wire where maximum strength and stiffness of the blank matter more than ductility. | 740 | 960 | 10 | 30 HRC | — |
What is 1.4305?
1.4305 (X8CrNiS18-9, S30300/303, SUS303) is the sulphur-added free-machining austenitic stainless, where 0.15–0.35 % S forms sulphide inclusions that break chips and cut tool wear. Annealed bar gives 260 MPa yield, 620 MPa tensile, 48 % elongation and 160 HB (84 HRB), with machinability 58 and service to 700 °C; it is supplied mainly as cold-drawn and ground bar in +AT, +AT+P and +C700 to +C900 for high-volume CNC turning. The sulphides reduce weldability (22), formability (42) and corrosion resistance (60), so avoid welded, drawn or cosmetic parts and specify 1.4301/304 or 1.4404/316L instead. 1.4305 has a density of 7.9 g/cm³ (0.285 lb/in³), heavier than 68% of stainless steel grades. It melts at 1,400°C (2,552 °F). 1.4305 has a yield strength of 260 MPa (37.7 ksi) and a tensile strength of 620 MPa (89.9 ksi) — weaker than 84% of stainless steel grades. Elongation at break is 48% and the elastic modulus is 193 GPa (28 Msi).
What is 1.4305 used for?
- precision turned fittings
- fasteners
- valve components
Advantages
- Easy to machine — 58/100, better than 97% of stainless steel grades
- Ductile — tolerates forming and impact — 48%, better than 85% of stainless steel grades
Limitations
- Hard to polish — 45/100, worse than 96% of stainless steel grades
- Difficult to weld — 22/100, worse than 94% of stainless steel grades
- Low strength — 260 MPa (37.7 ksi), worse than 84% of stainless steel grades
1.4305 properties
Typical room-temperature values for 1.4305-+AT; bars are the position among stainless steel grades.
Physical3
1.4305 has a density of 7.9 g/cm³ (0.285 lb/in³), heavier than 68% of stainless steel grades. It melts at 1,400°C (2,552 °F).
Mechanical14
1.4305 has a yield strength of 260 MPa (37.7 ksi) and a tensile strength of 620 MPa (89.9 ksi) — weaker than 84% of stainless steel grades. Elongation at break is 48% and the elastic modulus is 193 GPa (28 Msi).
Thermal6
1.4305 is rated for continuous service to 700°C (1,292 °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 16.5 µm/m·K (9.17 µin/in·°F).
Electrical3
1.4305 conducts electricity at 2.4 % IACS, better than 67% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is good (60/100), worse than 58% of stainless steel grades.
Sustainability4
Producing a kilogram of 1.4305 takes about 54 MJ of energy and emits 4.5 kg of CO₂ — less than 59% of stainless steel grades. Typical recycled content is 70%.
Manufacturability7
1.4305's machinability is good (58/100, better than 97% of stainless steel grades); weldability poor (22/100); formability fair (42/100).
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. 1.4305 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 1.4305
Is 1.4305 easy to machine?
The benchmark free-machining stainless: run 60–100 m/min HSS or 150–250 m/min carbide with sharp positive-rake tools, good chip flow and generous coolant; expect ~1.5–2× the material removal rate of 304 with far better tool life.
Can 1.4305 be welded?
Not recommended — 0.15–0.35 % S promotes solidification (hot) cracking; if unavoidable, use 308L/309L filler, low heat input, no filler-free autogenous welds, and accept reduced corrosion resistance.
Can 1.4305 be formed, bent or molded?
Limited cold formability: gentle bends with large radii only, avoid heavy heading, thread rolling or deep drawing; hot work 1150–1250 °C then solution anneal 1010–1120 °C and water quench.
1.4305 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 |
|---|---|---|
| CEN 10088-3 max | ≤ 0.1 | 0.06 |
| Si | ≤ 1 | 0.5 |
| Mncombines with S as MnS chip breakers | ≤ 2 | 1.3 |
| P | ≤ 0.05 | 0.03 |
| Sintentional free-machining addition | 0.15 – 0.35 | 0.25 |
| Cr | 17 – 19 | 18 |
| Ni | 8 – 10 | 9 |
| Cu | ≤ 1 | 0.4 |
| Mooptional/residual (AISI 303 allows ≤0.60 %) | ≤ 0.6 | |
| Nresidual limit per EN 10088-3 | ≤ 0.11 | 0.04 |
| Fe | balance |
What surface finishes work on 1.4305?
Passivate per ASTM A967 (citric or nitric) after machining to remove smeared sulphides; electroplating and PVD work with proper activation, but mirror polishing and electropolishing reveal sulphide pits — use 304/316 if cosmetic finish is critical.
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 1.4305 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- S30300
- AISI / SAE
- 303
- EN / DIN / Werkstoff-Nr.
- X8CrNiS18-9
- GB (China)
- Y1Cr18Ni9
- JIS
- SUS303
How much does 1.4305 cost?
1.4305 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.
1.4305 — frequently asked
What is 1.4305 used for?
1.4305 is typically used for precision turned fittings, fasteners and valve components. In short: best-machining austenitic stainless; not recommended for welding; turning-optimised 304 variant.
What is the yield strength of 1.4305?
1.4305 has a typical yield strength of 260 MPa (37.7 ksi) and a tensile strength of 620 MPa (89.9 ksi) — weaker than 84% of stainless steel grades. Strength varies by condition: see the 5 listed tempers.
Is 1.4305 easy to machine?
Reasonably — machinability is rated good (58/100, better than 97% of stainless steel grades). The benchmark free-machining stainless: run 60–100 m/min HSS or 150–250 m/min carbide with sharp positive-rake tools, good chip flow and generous coolant; expect ~1.5–2× the material removal rate of 304 with far better tool life.
Can 1.4305 be welded?
Not readily — weldability is rated poor (22/100). Not recommended — 0.15–0.35 % S promotes solidification (hot) cracking; if unavoidable, use 308L/309L filler, low heat input, no filler-free autogenous welds, and accept reduced corrosion resistance.
What surface finishes work on 1.4305?
Passivate per ASTM A967 (citric or nitric) after machining to remove smeared sulphides; electroplating and PVD work with proper activation, but mirror polishing and electropolishing reveal sulphide pits — use 304/316 if cosmetic finish is critical.
Can 1.4305 be formed, bent or molded?
Limited cold formability: gentle bends with large radii only, avoid heavy heading, thread rolling or deep drawing; hot work 1150–1250 °C then solution anneal 1010–1120 °C and water quench.
What is the maximum service temperature of 1.4305?
1.4305 is rated for continuous use to about 700°C (1,292 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does 1.4305 cost?
1.4305 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
- EN 10088-3 Stainless steels — Technical delivery conditions for semi-finished products, bars, rods, wire, sections — CEN (2014)
- ASTM A582/A582M Free-Machining Stainless Steel Bars — ASTM (2021)
- GB/T 1220 — SAC (2007)
- JIS G 4303 Stainless steel bars (SUS303) — JSA (2012)
- ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- Outokumpu / Sandvik free-machining austenitic bar datasheets (4305 / 303) — Outokumpu; Sandvik (2023)
- (SMM) / Mysteel — SMM; Mysteel (2026)
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.