Stainless Steel 1.4598-AT
Precip hard · default condition
EN 1.4598
Standard stock condition for hot-rolled/peeled bar and for parts needing maximum corrosion resistance and ductility.
Values for the AT condition
Other 1.4598 tempers and conditions
1.4598 is listed in 6 conditions; see the grade overview at 1.4598.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
ATDefaultThis page solution annealed (softened, water quenched) | Standard stock condition for hot-rolled/peeled bar and for parts needing maximum corrosion resistance and ductility. | 240 | 580 | 35 | 165 HB | — |
peeled / centreless ground and polished bar (annealed base) | Choose when h7/h8 diameter tolerance and a defect-free surface are needed on solution-annealed stock. | 240 | 580 | 35 | 165 HB | 2.3 % IACS |
lightly cold drawn / smooth-turned bar (annealed + skin pass) | Pick for h9/h11 tolerance bar where near-annealed properties and good corrosion resistance must be kept. | 350 | 620 | 28 | 185 HB | 2.3 % IACS |
cold drawn to Rm ≥ 700 MPa | Entry-level cold-drawn strength class for shafts and fasteners with good straightness and chip control. | 420 | 760 | 20 | 215 HB | — |
cold drawn to Rm ≥ 800 MPa | Mid strength class for small-diameter automatic-lathe bar needing higher yield without heat treatment. | 520 | 860 | 16 | 23 HRC | — |
cold drawn to Rm ≥ 900 MPa | Highest standard cold-drawn class, for small bar and pins where strength matters more than ductility. | 620 | 960 | 12 | 28 HRC | — |
What is 1.4598-AT?
1.4598-AT is 1.4598 in the AT condition — standard stock condition for hot-rolled/peeled bar and for parts needing maximum corrosion resistance and ductility. 1.4598-AT has a yield strength of 240 MPa (34.8 ksi) and a tensile strength of 580 MPa (84.1 ksi) — weaker than 96% of stainless steel grades. Elongation at break is 35% and the elastic modulus is 200 GPa (29 Msi). 1.4598-AT has a density of 8 g/cm³ (0.289 lb/in³), heavier than 92% of stainless steel grades. It melts at 1,380°C (2,516 °F).
Advantages
- Easy to machine — 68/100, better than 98% of stainless steel grades
Limitations
- Hard to polish — 35/100, worse than 100% of stainless steel grades
- Low strength — 240 MPa (34.8 ksi), worse than 96% of stainless steel grades
- Difficult to weld — 30/100, worse than 88% of stainless steel grades
- Limited service temperature — 400°C (752 °F), worse than 78% of stainless steel grades
1.4598-AT properties
Typical room-temperature values for 1.4598-AT; 13 are specific to this condition. Other listed values are 1.4598 reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
1.4598-AT has a density of 8 g/cm³ (0.289 lb/in³), heavier than 92% of stainless steel grades. It melts at 1,380°C (2,516 °F).
Mechanical16
1.4598-AT has a yield strength of 240 MPa (34.8 ksi) and a tensile strength of 580 MPa (84.1 ksi) — weaker than 96% of stainless steel grades. Elongation at break is 35% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
1.4598-AT is rated for continuous service to 400°C (752 °F). It conducts heat at 15 W/m·K (8.67 BTU/hr·ft·°F), worse than 59% of stainless steel grades. Thermal expansion is 16.5 µm/m·K (9.17 µin/in·°F).
Electrical3
1.4598-AT conducts electricity at 2.3 % IACS, better than 55% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is very good (70/100), better than 68% of stainless steel grades.
Sustainability4
Producing a kilogram of 1.4598-AT takes about 55 MJ of energy and emits 4.8 kg of CO₂ — more than 50% of stainless steel grades. Typical recycled content is 65%.
Manufacturability7
1.4598-AT's machinability is good (68/100, better than 98% of stainless steel grades); weldability poor (30/100); formability fair (50/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 1.4598-AT
Is 1.4598 easy to machine?
Excellent for CNC/Swiss turning — run ~1.5–1.8× the speed of 316L with sharp positive geometry, high-pressure coolant and no dwelling to avoid work hardening.
Can 1.4598 be welded?
Not recommended for structural welds: the 0.15–0.35% S causes hot cracking; if unavoidable use low heat input, 316L/309L filler and accept reduced properties.
Can 1.4598 be formed, bent or molded?
Suitable for turning, knurling, rolling of threads and mild upsetting; avoid deep drawing or tight cold bends because sulphide stringers open as edge cracks.
What surface finishes work on 1.4598?
Passivate per ASTM A967 (citric preferred, as nitric can attack sulphides); electropolishing and mirror polishing give a slightly pitted look — not for cosmetic Class-A surfaces.
1.4598 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 |
|---|---|---|
| Clow-carbon, limits sensitisation | ≤ 0.03 | 0.02 |
| Si | ≤ 1 | 0.5 |
| Mncombines with S as MnS chip breakers | ≤ 2 | 1.5 |
| P | ≤ 0.05 | 0.03 |
| Sdeliberate free-machining addition | 0.15 – 0.35 | 0.25 |
| Cr | 16 – 18.5 | 17 |
| Ni | 10 – 13 | 11 |
| Mo | 1.8 – 2.5 | 2.1 |
| Cuimproves chip formation and cold heading | 1 – 2 | 1.5 |
| N | ≤ 0.11 | 0.05 |
| Fe | balance | — |
1.4598-AT — frequently asked
What is 1.4598-AT used for?
1.4598-AT is typically used for precision machined fittings, valve parts and pump components. In short: free-machining 316L alternative; screw-machine stainless bar; mo-bearing, high-throughput turning.
What is the yield strength of 1.4598-AT?
1.4598-AT has a typical yield strength of 240 MPa (34.8 ksi) and a tensile strength of 580 MPa (84.1 ksi) — weaker than 96% of stainless steel grades. Strength varies by condition: see the 6 listed tempers.
Is 1.4598-AT easy to machine?
Reasonably — machinability is rated good (68/100, better than 98% of stainless steel grades). Excellent for CNC/Swiss turning — run ~1.5–1.8× the speed of 316L with sharp positive geometry, high-pressure coolant and no dwelling to avoid work hardening.
Can 1.4598-AT be welded?
Not readily — weldability is rated poor (30/100). Not recommended for structural welds: the 0.15–0.35% S causes hot cracking; if unavoidable use low heat input, 316L/309L filler and accept reduced properties.
What surface finishes work on 1.4598-AT?
Passivate per ASTM A967 (citric preferred, as nitric can attack sulphides); electropolishing and mirror polishing give a slightly pitted look — not for cosmetic Class-A surfaces.
Can 1.4598-AT be formed, bent or molded?
Suitable for turning, knurling, rolling of threads and mild upsetting; avoid deep drawing or tight cold bends because sulphide stringers open as edge cracks.
What is the maximum service temperature of 1.4598-AT?
1.4598-AT is rated for continuous use to about 400°C (752 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 1.4598-AT and 1.4598-C900?
AT is the default condition — standard stock condition for hot-rolled/peeled bar and for parts needing maximum corrosion resistance and ductility. C900: highest standard cold-drawn class, for small bar and pins where strength matters more than ductility. Yield strength is 240 MPa in AT versus 620 MPa in C900.
Sources
- EN 10088-1 Stainless steels — List of stainless steels — CEN (2014)
- EN 10088-3 Stainless steels — Semi-finished products, bars, rods, wire, sections — CEN (2014)
- ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels and High-Performance Alloys — ASM International (1990)
- ASM Handbook Vol. 13B — Corrosion: Materials — ASM International (2005)
- Free-machining austenitic stainless bar datasheets (Ugitech/Sandvik/Outokumpu class data) — producers (2023)
- (Mysteel / SMM / 1688 ) — Mysteel, SMM (2025)
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.