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Steel SKH2 QT-STEAM

Finish state

JIS SKH2 · AISI/SAE T1

Choose for drills/taps where the oxide film holds lubricant and reduces built-up edge on steel.

High cost $$$$

Values for the QT-STEAM condition

Other SKH2 tempers and conditions

SKH2 is listed in 6 conditions; see the grade overview at SKH2.

Compare all 6 conditionsHide
Condition · open for datasheetBest forYield MPaTensile MPaElong. %HardnessConductivity
ADefault
Solution annealed
Standard mill condition for machining tool blanks before hardening.54088018240 HB—
Hardened & triple tempered to 60–62 HRC
Lower-hardness, tougher setting for interrupted cuts, large broaches, form tools and cold-work punches.—2,100—61 HRC—
QT-STEAMThis page
Hardened & tempered + steam-oxide (blue) surface treatment
Choose for drills/taps where the oxide film holds lubricant and reduces built-up edge on steel.2,1002,3000.563 HRC2.8 % IACS
Hardened & tempered + nitrided / PVD coated
Surface-engineered condition for higher cutting speeds and abrasive workpieces; core properties unchanged.2,1502,3500.464 HRC2.8 % IACS
Hardened & triple tempered to 62–64 HRC
Standard working hardness for general-purpose lathe tools, milling cutters and drills.—2,250—63 HRC—
Hardened & triple tempered to 64–66 HRC
Maximum wear resistance and red hardness for finishing tools on soft workpieces; least tough — avoid shock loading.—2,300—65 HRC—

What is SKH2 QT-STEAM?

SKH2 QT-STEAM is SKH2 supplied in the QT-STEAM condition — choose for drills/taps where the oxide film holds lubricant and reduces built-up edge on steel. SKH2 QT-STEAM has a yield strength of 2,100 MPa (305 ksi) and a tensile strength of 2,300 MPa (334 ksi) — stronger than 100% of steel grades. Elongation at break is 0.5% and the elastic modulus is 217 GPa (31.5 Msi). SKH2 QT-STEAM has a density of 8.67 g/cm³ (0.313 lb/in³), heavier than 99% of steel grades. It melts at 1,290°C (2,354 °F). A is the default condition FabDigit quotes; QT-STEAM is available on request or by drawing note.

Advantages

  • High strength — 2,100 MPa (305 ksi), better than 100% of steel grades
  • High service temperature — 580°C (1,076 °F), better than 97% of steel grades
  • Polishes to a fine finish — 80/100, better than 97% of steel grades
  • Good corrosion resistance — 30/100, better than 95% of steel grades

Limitations

  • Limited ductility — 0.5%, worse than 100% of steel grades
  • Difficult to machine — 5/100, worse than 100% of steel grades
  • Limited formability — 2/100, worse than 100% of steel grades
  • Difficult to weld — 8/100, worse than 99% of steel grades
  • Poor heat conductor — 19 W/m·K (11 BTU/hr·ft·°F), worse than 97% of steel grades

SKH2 QT-STEAM properties

Typical room-temperature values for SKH2 QT-STEAM; 22 are specific to this condition. Other listed values are SKH2 reference data and may not represent this condition. Bars are the position among steel grades.

Physical3

SKH2 QT-STEAM has a density of 8.67 g/cm³ (0.313 lb/in³), heavier than 99% of steel grades. It melts at 1,290°C (2,354 °F).

Density8.67 g/cm³0.31 lb/in³
Melting Point (Solidus)1,290°C2,354 °F
Liquidus Temperature1,430°C2,606 °F

Mechanical14

SKH2 QT-STEAM has a yield strength of 2,100 MPa (305 ksi) and a tensile strength of 2,300 MPa (334 ksi) — stronger than 100% of steel grades. Elongation at break is 0.5% and the elastic modulus is 217 GPa (31.5 Msi).

Elastic (Young's) Modulus217 GPa31.5 Msi
Shear Modulus85 GPa12.3 Msi
Bulk Modulus167 GPa24.2 Msi
Poisson's Ratio0.28
Tensile Strength (Ultimate)2,300 MPa334 ksi
Yield Strength (0.2% offset)2,100 MPa305 ksi
Elongation at Break0.5%
Reduction in Area1%
Compressive Strength3,400 MPa493 ksi
Shear Strength1,450 MPa210 ksi
Charpy V-Notch Impact (RT)4 J3 ft·lbf
Hardness, Brinell640 HB
Hardness, Rockwell B99 HRB
Hardness, Vickers770 HV

Thermal6

SKH2 QT-STEAM is rated for continuous service to 580°C (1,076 °F). It conducts heat at 19 W/m·K (11 BTU/hr·ft·°F), worse than 97% of steel grades. Thermal expansion is 10.6 µm/m·K (5.89 µin/in·°F).

Thermal Conductivity19 W/m·K11 BTU/hr·ft·°F
Specific Heat Capacity420 J/kg·K0.1 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)10.6 µm/m·K5.9 µin/in·°F
Latent Heat of Fusion250 J/g107 BTU/lb
Max Service Temperature (continuous)580°C1,076 °F
Min Service Temperature-60°C-76 °F

Electrical3

SKH2 QT-STEAM conducts electricity at 2.8 % IACS, worse than 94% of steel grades.

Electrical Conductivity2.8 % IACS
Electrical Resistivity6.2×10⁻⁷ Ω·m24.4 µΩ·in
Magnetic Responseferromagnetic

Chemical & Environmental3

Corrosion resistance is poor (30/100), better than 95% of steel grades.

Galvanic Potential (seawater, vs SCE)-0.45 V
Corrosion ResistancePoor30/100
Chemical Resistance SummaryNot stainless: rusts in humid air, water and chlorinated coolants; resists dry mineral oils and cutting fluids; attacked by acids and salt spray — store oiled or with a phosphate/oxide finish.

Sustainability4

Producing a kilogram of SKH2 QT-STEAM takes about 48 MJ of energy and emits 3.4 kg of CO₂ — more than 93% of steel grades. Typical recycled content is 35%.

Embodied Energy (primary production)48 MJ/kg20,636 BTU/lb
Embodied Carbon (primary production)3.4 kg CO₂/kg
Embodied Water70 L/kg8.4 gal/lb
Typical Recycled Content35%

Manufacturability7

SKH2 QT-STEAM's machinability is not recommended (5/100, worse than 100% of steel grades); weldability not recommended (8/100); formability not recommended (2/100).

MachinabilityNot recommended5/100
Machinability Rating (AISI 1212 = 100 %)5%
WeldabilityNot recommended8/100
Formability (cold)Not recommended2/100
Brazeability / SolderabilityGood60/100
PolishabilityVery good80/100
Anodizing Responsen/a — ferrous alloy; use black oxide, steam-oxide, nitriding or PVD (TiN/TiCN/TiAlN) instead

Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.

Working with SKH2 QT-STEAM

Is SKH2 easy to machine?

Machine only in the annealed condition (≤255 HB) with sharp cobalt-HSS or coated carbide, rigid setups and flood coolant; hardened tools require grinding (Al₂O₃/CBN) or EDM.

Can SKH2 be welded?

Poor weldability — repair welding only with matching HSS filler, 500–550 °C preheat/interpass and immediate re-temper at 550–560 °C to avoid quench cracks.

Can SKH2 be formed, bent or molded?

Hot forge 1100–1150 °C, finish above 950 °C and cool slowly in furnace/vermiculite followed by 850–870 °C anneal; no meaningful cold forming.

What surface finishes work on SKH2?

Hardened surfaces take a mirror polish; protect with black oxide, steam blue, phosphate or PVD TiN/TiAlN — not anodizable and not corrosion-resistant bare.

SKH2 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.

ElementSpec limit (wt %)Nominal
C0.73 – 0.830.78
Si≤ 0.450.25
Mn≤ 0.40.25
P≤ 0.03—
S≤ 0.03—
Cr3.8 – 4.54.15
Wprincipal red-hardness element17 – 1918
V0.8 – 1.21.1
Moresidual; not a specified alloying addition in SKH2≤ 0.3—
Febalance—

SKH2 QT-STEAM — frequently asked

What is SKH2 QT-STEAM used for?

SKH2 QT-STEAM is typically used for drills, reamers and lathe tools. In short: classic tungsten HSS; well-known T1 equivalent; lower cost than cobalt HSS.

What is the yield strength of SKH2 QT-STEAM?

SKH2 QT-STEAM has a typical yield strength of 2,100 MPa (305 ksi) and a tensile strength of 2,300 MPa (334 ksi) — stronger than 100% of steel grades. Strength varies by condition: see the 6 listed tempers.

Is SKH2 QT-STEAM easy to machine?

Not especially — machinability is rated not recommended (5/100, worse than 100% of steel grades). Machine only in the annealed condition (≤255 HB) with sharp cobalt-HSS or coated carbide, rigid setups and flood coolant; hardened tools require grinding (Al₂O₃/CBN) or EDM.

Can SKH2 QT-STEAM be welded?

Not readily — weldability is rated not recommended (8/100). Poor weldability — repair welding only with matching HSS filler, 500–550 °C preheat/interpass and immediate re-temper at 550–560 °C to avoid quench cracks.

What surface finishes work on SKH2 QT-STEAM?

Hardened surfaces take a mirror polish; protect with black oxide, steam blue, phosphate or PVD TiN/TiAlN — not anodizable and not corrosion-resistant bare.

Can SKH2 QT-STEAM be formed, bent or molded?

Hot forge 1100–1150 °C, finish above 950 °C and cool slowly in furnace/vermiculite followed by 850–870 °C anneal; no meaningful cold forming.

What is the maximum service temperature of SKH2 QT-STEAM?

SKH2 QT-STEAM is rated for continuous use to about 580°C (1,076 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.

What is the difference between SKH2-A and SKH2 QT-NIT?

A is the default condition — standard mill condition for machining tool blanks before hardening. QT-NIT: surface-engineered condition for higher cutting speeds and abrasive workpieces; core properties unchanged. Yield strength is 540 MPa in A versus 2,150 MPa in QT-NIT.

Sources

  1. JIS G4403 High Speed Tool Steel Materials — JSA (2015)
  2. GB/T 9943 (W18Cr4V) — SAC (2008)
  3. ASTM A600 Standard Specification for Tool Steel High Speed (T1) — ASTM (2016)
  4. ASM Handbook Vol.1: Properties and Selection — Irons, Steels, and High-Performance Alloys — ASM International (1990)
  5. ASM Handbook Vol.16: Machining — ASM International (1989)
  6. High speed steel T1/W18Cr4V technical data — Böhler / Hitachi Metals (typical) (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.