Steel L2 Hard
Supply condition
AISI/SAE L2 · UNS T61202
Hard = hardened
L2 austenitized ~845–870 °C and oil quenched to full martensitic hardness with only a minimal stress-relief temper, giving maximum hardness and wear resistance but low toughness; used for chisels, punches, knurls and shear blades that are ground to size.
Values for the Hard condition
Other L2 tempers and conditions
L2 is listed in 9 conditions; see the grade overview at L2.
Compare all 9 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
ANNDefault Annealed | Standard stocked condition for machining tools and parts before hardening. | 510 | 710 | 25 | 183 HB | — |
Hot rolled | Mill-finish rolled bar taken for re-forging or as-purchased blanks that will be annealed then hardened. | 560 | 850 | 18 | 22 HRC | 7.8 % IACS |
Cold Drawn, annealed base | Choose for close-tolerance shafting and tool blanks needing minimal cleanup before hardening. | 620 | 790 | 16 | 17 HRC | 7.8 % IACS |
Oil quenched + tempered 650 °C | Pre-hardened machinable condition for structural machine components that will not be re-heat-treated. | 760 | 930 | 20 | 31 HRC | — |
Oil quenched + tempered 540 °C | High-toughness machine-part condition for shafts, gears and springs made from the lower-carbon L2 variant. | 1,105 | 1,240 | 14 | 40 HRC | — |
Oil quenched + tempered 425 °C | Tough working hardness for chisels, spindles, arbors and impact-loaded tooling. | 1,380 | 1,550 | 10 | 46 HRC | — |
Oil quenched + tempered 315 °C | Balanced hardness/toughness for shear blades, forming dies and heavily loaded punches. | 1,550 | 1,790 | 8 | 52 HRC | — |
Oil quenched + tempered 205 °C | Maximum hardness condition for punches, blanking dies, taps and knurls where wear resistance dominates. | 1,790 | 2,070 | 5 | 56 HRC | — |
HardThis page Hardened | L2 austenitized ~845–870 °C and oil quenched to full martensitic hardness with only a minimal stress-relief temper, giving maximum hardness and wear resistance but low toughness; used for chisels, punches, knurls and shear blades that are ground to size. | 1,800 | 2,150 | 2 | 61 HRC | 33 W/m·K |
What is L2 Hard?
L2 Hard is L2 supplied in the Hard condition — l2 austenitized ~845–870 °C and oil quenched to full martensitic hardness with only a minimal stress-relief temper, giving maximum hardness and wear resistance but low toughness; used for chisels, punches, knurls and shear blades that are ground to size. L2 Hard has a yield strength of 1,800 MPa (261 ksi) and a tensile strength of 2,150 MPa (312 ksi) — stronger than 99% of steel grades. Elongation at break is 2% and the elastic modulus is 207 GPa (30 Msi). L2 Hard has a density of 7.86 g/cm³ (0.284 lb/in³), heavier than 90% of steel grades. It melts at 1,420°C (2,588 °F). ANN is the default condition FabDigit quotes; Hard is available on request or by drawing note.
Advantages
- High strength — 1,800 MPa (261 ksi), better than 99% of steel grades
- Polishes to a fine finish — 80/100, better than 97% of steel grades
Limitations
- Difficult to machine — 8/100, worse than 100% of steel grades
- Limited ductility — 2%, worse than 99% of steel grades
- Limited service temperature — 175°C (347 °F), worse than 99% of steel grades
- Difficult to weld — 8/100, worse than 99% of steel grades
- Limited formability — 3/100, worse than 99% of steel grades
L2 Hard properties
Typical room-temperature values for L2 Hard; 33 are specific to this condition. Other listed values are L2 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
L2 Hard has a density of 7.86 g/cm³ (0.284 lb/in³), heavier than 90% of steel grades. It melts at 1,420°C (2,588 °F).
Mechanical15
L2 Hard has a yield strength of 1,800 MPa (261 ksi) and a tensile strength of 2,150 MPa (312 ksi) — stronger than 99% of steel grades. Elongation at break is 2% and the elastic modulus is 207 GPa (30 Msi).
Thermal6
L2 Hard is rated for continuous service to 175°C (347 °F). It conducts heat at 33 W/m·K (19.1 BTU/hr·ft·°F), worse than 80% of steel grades. Thermal expansion is 12.4 µm/m·K (6.89 µin/in·°F).
Electrical3
L2 Hard conducts electricity at 7.8 % IACS, worse than 57% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of L2 Hard takes about 34 MJ of energy and emits 2.5 kg of CO₂ — more than 82% of steel grades. Typical recycled content is 40%.
Manufacturability8
L2 Hard's machinability is not recommended (8/100, worse than 100% of steel grades); weldability not recommended (8/100); formability not recommended (3/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with L2 Hard
Is L2 easy to machine?
Machine in the annealed condition (~65 % of AISI 1212) with sharp carbide or M2 HSS tooling; above 45 HRC switch to grinding, EDM or CBN.
Can L2 be welded?
Not intended for welding — if repair is unavoidable, preheat 300–400 °C, use a matching or low-hydrogen Cr-V filler and re-temper immediately.
Can L2 be formed, bent or molded?
Hot work at 900–1080 °C with slow cooling and a full spheroidize anneal (760–790 °C, slow cool) afterwards; cold forming is limited to mild bending of annealed stock.
What surface finishes work on L2?
Fine grain permits a good ground and polished finish; protect the bare surface by oiling, black oxide, phosphating, nitriding or hard chrome — no anodizing.
L2 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 level selected by application: ~0.50 % for tough machine parts, ~1.00 % for wear tooling | 0.45 – 1 | 0.7 |
| Mn | 0.1 – 0.9 | 0.5 |
| Si | ≤ 0.5 | 0.25 |
| Cr | 0.7 – 1.2 | 1 |
| Vgrain refiner | 0.1 – 0.3 | 0.2 |
| P | ≤ 0.03 | — |
| S | ≤ 0.03 | — |
| Fe | balance | — |
L2 Hard — frequently asked
What is L2 Hard used for?
L2 Hard is typically used for arbors and collets, cutting tools, machine tool parts, gauges and wear-resistant pins and rolls. In short: tough oil-hardening Cr-V steel; wide tempering range; fine grain, good polish.
What is the yield strength of L2 Hard?
L2 Hard has a typical yield strength of 1,800 MPa (261 ksi) and a tensile strength of 2,150 MPa (312 ksi) — stronger than 99% of steel grades. Strength varies by condition: see the 9 listed tempers.
Is L2 Hard easy to machine?
Not especially — machinability is rated not recommended (8/100, worse than 100% of steel grades). Machine in the annealed condition (~65 % of AISI 1212) with sharp carbide or M2 HSS tooling; above 45 HRC switch to grinding, EDM or CBN.
Can L2 Hard be welded?
Not readily — weldability is rated not recommended (8/100). Not intended for welding — if repair is unavoidable, preheat 300–400 °C, use a matching or low-hydrogen Cr-V filler and re-temper immediately.
What surface finishes work on L2 Hard?
Fine grain permits a good ground and polished finish; protect the bare surface by oiling, black oxide, phosphating, nitriding or hard chrome — no anodizing.
Can L2 Hard be formed, bent or molded?
Hot work at 900–1080 °C with slow cooling and a full spheroidize anneal (760–790 °C, slow cool) afterwards; cold forming is limited to mild bending of annealed stock.
What is the maximum service temperature of L2 Hard?
L2 Hard is rated for continuous use to about 175°C (347 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between L2-ANN and L2 Hard?
ANN is the default condition — standard stocked condition for machining tools and parts before hardening. Hard: l2 austenitized ~845–870 °C and oil quenched to full martensitic hardness with only a minimal stress-relief temper, giving maximum hardness and wear resistance but low toughness; used for chisels, punches, knurls and shear blades that are ground to size. Yield strength is 510 MPa in ANN versus 1,800 MPa in Hard.
Sources
- ASTM A681 — Standard Specification for Tool Steels Alloy — ASTM International (2022)
- ASM Handbook Vol. 1: Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- Tool Steels, 5th Edition (Roberts, Krauss, Kennedy) — ASM International (1998)
- ASM Handbook Vol. 16: Machining — ASM International (1989)
- UNS T61202 alloy record — SAE/ASTM Unified Numbering System (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.