Stainless Steel AUS-8 Annealed
Temper · default condition
The as-supplied condition for knife blanks: soft enough to stamp, laser-cut, drill and grind before heat treatment.
Values for the Annealed condition
Other AUS-8 tempers and conditions
AUS-8 is listed in 5 conditions; see the grade overview at AUS-8.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
AnnealedDefaultThis page mill soft-annealed strip/plate for blanking and machining | The as-supplied condition for knife blanks: soft enough to stamp, laser-cut, drill and grind before heat treatment. | 450 | 760 | 18 | 225 HB | — |
Cold rolled | Precision-rolled thin strip supplied slightly harder than full anneal for clean stamping of thin blades and razor blanks. | 650 | 900 | 10 | 28 HRC | 3 % IACS |
hardened and tempered for maximum toughness | Choose for choppers, machetes, dive knives and thick-spine tools where chip resistance beats edge holding. | 1,600 | 1,900 | 3 | 56 HRC | — |
standard knife hardening (≈1050–1070 °C austenitize, 180–200 °C temper) | The mainstream production-knife condition: best balance of edge retention, toughness and easy field sharpening. | 1,750 | 2,050 | 2 | 58 HRC | — |
Q&T + cryogenic 59–61 HRC | Sub-zero treatment converts retained austenite for peak hardness and edge stability; toughness and corrosion margin drop, so keep edges thicker. | 1,850 | 2,150 | 1.5 | 60 HRC | — |
What is AUS-8 Annealed?
AUS-8 Annealed is AUS-8 in the Annealed temper — the as-supplied condition for knife blanks: soft enough to stamp, laser-cut, drill and grind before heat treatment. AUS-8 Annealed has a yield strength of 450 MPa (65.3 ksi) and a tensile strength of 760 MPa (110 ksi) — stronger than 70% of stainless steel grades. Elongation at break is 18% and the elastic modulus is 200 GPa (29 Msi). AUS-8 Annealed has a density of 7.75 g/cm³ (0.28 lb/in³), lighter than 65% of stainless steel grades. It melts at 1,400°C (2,552 °F).
Advantages
- High electrical conductivity — 3 % IACS, better than 95% of stainless steel grades
- Conducts heat well — 24 W/m·K (13.9 BTU/hr·ft·°F), better than 81% of stainless steel grades
Limitations
- Difficult to weld — 20/100, worse than 95% of stainless steel grades
- Low fracture toughness — 60 MPa·√m (54.6 ksi·√in), worse than 88% of stainless steel grades
- Limited ductility — 18%, worse than 83% of stainless steel grades
- Needs corrosion protection — 48/100, worse than 80% of stainless steel grades
- Limited service temperature — 400°C (752 °F), worse than 78% of stainless steel grades
AUS-8 Annealed properties
Typical room-temperature values for AUS-8 Annealed; 14 are specific to this condition. Other listed values are AUS-8 reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
AUS-8 Annealed has a density of 7.75 g/cm³ (0.28 lb/in³), lighter than 65% of stainless steel grades. It melts at 1,400°C (2,552 °F).
Mechanical16
AUS-8 Annealed has a yield strength of 450 MPa (65.3 ksi) and a tensile strength of 760 MPa (110 ksi) — stronger than 70% of stainless steel grades. Elongation at break is 18% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
AUS-8 Annealed is rated for continuous service to 400°C (752 °F). It conducts heat at 24 W/m·K (13.9 BTU/hr·ft·°F), better than 81% of stainless steel grades. Thermal expansion is 10.4 µm/m·K (5.78 µin/in·°F).
Electrical3
AUS-8 Annealed conducts electricity at 3 % IACS, better than 95% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is fair (48/100), worse than 80% of stainless steel grades.
Sustainability4
Producing a kilogram of AUS-8 Annealed takes about 53 MJ of energy and emits 5 kg of CO₂ — less than 67% of stainless steel grades. Typical recycled content is 35%.
Manufacturability8
AUS-8 Annealed's machinability is fair (40/100, better than 72% of stainless steel grades); weldability poor (20/100); formability fair (35/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with AUS-8 Annealed
Is AUS-8 easy to machine?
Machine, drill and profile only in the annealed state with sharp carbide and rigid setups (~45 % of 1212); once hardened, work by CBN/diamond grinding or EDM only.
Can AUS-8 be welded?
Poor weldability — 0.75 % C martensitic steel cracks readily; if unavoidable preheat 250–300 °C, use 309/312 filler and temper immediately, expect a soft/brittle HAZ.
Can AUS-8 be formed, bent or molded?
Blank, laser or waterjet cut and lightly bend in the annealed condition; hot forge 1050–1150 °C, never below ~900 °C, and always slow-cool/anneal after forging.
What surface finishes work on AUS-8?
Grind, then passivate (citric or nitric per ASTM A967) after hardening; takes a fine satin or mirror polish, and accepts stonewash, bead blast, black oxide or PVD/DLC coatings applied below the tempering temperature.
AUS-8 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 | 0.7 – 0.75 | 0.73 |
| Si | ≤ 1 | 0.4 |
| Mn | ≤ 0.5 | 0.4 |
| P | ≤ 0.04 | — |
| S | ≤ 0.03 | — |
| Niaustenite stabiliser, aids toughness | ≤ 0.49 | 0.3 |
| Cr | 13 – 14.5 | 13.75 |
| Mo | 0.1 – 0.31 | 0.2 |
| Vgrain refinement, fine carbides | 0.1 – 0.26 | 0.18 |
| Fe | balance | — |
AUS-8 Annealed — frequently asked
What is AUS-8 Annealed used for?
AUS-8 Annealed is typically used for mid-range production knives, multi-tools and kitchen cutlery. In short: easy-sharpening mid-range blade steel; best formability in family; tougher than 440C-class.
What is the yield strength of AUS-8 Annealed?
AUS-8 Annealed has a typical yield strength of 450 MPa (65.3 ksi) and a tensile strength of 760 MPa (110 ksi) — stronger than 70% of stainless steel grades. Strength varies by condition: see the 5 listed tempers.
Is AUS-8 Annealed easy to machine?
Not especially — machinability is rated fair (40/100, better than 72% of stainless steel grades). Machine, drill and profile only in the annealed state with sharp carbide and rigid setups (~45 % of 1212); once hardened, work by CBN/diamond grinding or EDM only.
Can AUS-8 Annealed be welded?
Not readily — weldability is rated poor (20/100). Poor weldability — 0.75 % C martensitic steel cracks readily; if unavoidable preheat 250–300 °C, use 309/312 filler and temper immediately, expect a soft/brittle HAZ.
What surface finishes work on AUS-8 Annealed?
Grind, then passivate (citric or nitric per ASTM A967) after hardening; takes a fine satin or mirror polish, and accepts stonewash, bead blast, black oxide or PVD/DLC coatings applied below the tempering temperature.
Can AUS-8 Annealed be formed, bent or molded?
Blank, laser or waterjet cut and lightly bend in the annealed condition; hot forge 1050–1150 °C, never below ~900 °C, and always slow-cool/anneal after forging.
What is the maximum service temperature of AUS-8 Annealed?
AUS-8 Annealed 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 AUS-8 Annealed and AUS-8-CR?
Annealed is the default condition — the as-supplied condition for knife blanks: soft enough to stamp, laser-cut, drill and grind before heat treatment. CR: precision-rolled thin strip supplied slightly harder than full anneal for clean stamping of thin blades and razor blanks. Yield strength is 450 MPa in Annealed versus 650 MPa in CR.
Sources
- AUS series stainless knife steel (AUS-6 / AUS-8 / AUS-10) data — Aichi Steel Corporation (2020)
- ASM Handbook Vol.1: Properties and Selection — Irons, Steels and High-Performance Alloys (martensitic stainless) — ASM International (1990)
- JIS G 4303 / G 4305 — Stainless steel bars and cold-rolled plates, sheets and strip — JSA (2021)
- ASTM A967 — Chemical Passivation Treatments for Stainless Steel Parts — ASTM (2017)
- Machinery's Handbook, machinability ratings for stainless steels — Industrial Press (2020)
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.