Steel M30
AISI/SAE M30 · UNS T11330
M30 (UNS T11330) is a cobalt-bearing molybdenum high-speed steel that adds red hardness over the standard M-series grades for higher-temperature cutting.
Reference datasheet — M30 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 ANN condition
M30 tempers and conditions
M30 is supplied in 5 conditions, soft to hard. ANN 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 |
|---|---|---|---|---|---|---|
Hardened & tempered | Choose when interrupted cuts or large tool sections need more toughness than peak hardness. | 62 HRC | 21 W/m·K | |||
ANNDefault Annealed | Standard as-supplied condition for machining tool blanks before hardening. | 590 | 900 | 15 | 235 HB | 24 W/m·K |
Annealed + ground/turned precision bar | Ready-to-use annealed bar with controlled diameter and surface for tool blank production. | 590 | 900 | 15 | 22 HRC | 2.9 % IACS |
Hot rolled | Mill-supplied intermediate form; must be spheroidize annealed before machining. | 800 | 1,080 | 8 | 34 HRC | 2.9 % IACS |
Hardened & tempered | Peak-hardness working condition for high-speed cutting tools where red hardness matters most. | 1,900 | 2,100 | 0.5 | 65 HRC | 21 W/m·K |
What is M30?
M30 (UNS T11330) is a cobalt-bearing molybdenum high-speed steel that adds red hardness over the standard M-series grades for higher-temperature cutting. It is used for tools that run hot or take heavy cuts, and is available as annealed, ground-annealed and hot-rolled bar, heat treated to 62 or 64 HRC. Annealed properties are 900 MPa tensile, 590 MPa yield, 15 % elongation, 235 HB, 217 GPa modulus and 24 W/m·K, with service to 480 °C. Cobalt content lowers toughness and raises cost against M2, weldability (15) and corrosion resistance (15) are poor; M33 or M34 give more hot hardness. M30 has a density of 8.03 g/cm³ (0.29 lb/in³), heavier than 96% of steel grades. It melts at 1,260°C (2,300 °F). M30 has a yield strength of 590 MPa (85.6 ksi) and a tensile strength of 900 MPa (131 ksi) — stronger than 76% of steel grades. Elongation at break is 15% and the elastic modulus is 217 GPa (31.5 Msi).
What is M30 used for?
- Heavy-duty lathe tools
- Milling cutters for hard materials
- High-speed drilling
Advantages
- Polishes to a fine finish — 75/100, better than 94% of steel grades
- High service temperature — 480°C (896 °F), better than 88% of steel grades
- High strength — 590 MPa (85.6 ksi), better than 76% of steel grades
Limitations
- High embodied carbon — 3.6 kg CO₂/kg, worse than 94% of steel grades
- Low electrical conductivity — 2.9 % IACS, worse than 93% of steel grades
- Difficult to weld — 15/100, worse than 91% of steel grades
- Poor heat conductor — 24 W/m·K (13.9 BTU/hr·ft·°F), worse than 90% of steel grades
- Limited formability — 15/100, worse than 87% of steel grades
M30 properties
Typical room-temperature values for M30-ANN; bars are the position among steel grades.
Physical3
M30 has a density of 8.03 g/cm³ (0.29 lb/in³), heavier than 96% of steel grades. It melts at 1,260°C (2,300 °F).
Mechanical15
M30 has a yield strength of 590 MPa (85.6 ksi) and a tensile strength of 900 MPa (131 ksi) — stronger than 76% of steel grades. Elongation at break is 15% and the elastic modulus is 217 GPa (31.5 Msi).
Thermal6
M30 is rated for continuous service to 480°C (896 °F). It conducts heat at 24 W/m·K (13.9 BTU/hr·ft·°F), worse than 90% of steel grades. Thermal expansion is 10.5 µm/m·K (5.83 µin/in·°F).
Electrical3
M30 conducts electricity at 2.9 % IACS, worse than 93% of steel grades.
Chemical & Environmental3
Corrosion resistance is poor (15/100), better than 75% of steel grades.
Sustainability4
Producing a kilogram of M30 takes about 55 MJ of energy and emits 3.6 kg of CO₂ — more than 94% of steel grades. Typical recycled content is 40%.
Manufacturability7
M30's machinability is fair (35/100, worse than 84% of steel grades); weldability poor (15/100); formability poor (15/100).
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 steel family
Yield strength against density for every steel grade FabDigit runs. M30 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with M30
Is M30 easy to machine?
Machine only in the annealed condition with rigid setups, sharp carbide or coated-carbide tooling and generous coolant; after hardening only grinding (CBN/SG-alumina wheels) and EDM are practical.
Can M30 be welded?
Essentially not weldable structurally; repair only by TIG/laser with matched HSS filler at 480–540 °C preheat followed by immediate temper, otherwise quench cracking is likely.
Can M30 be formed, bent or molded?
Hot forge 1050–1150 °C, stop above 900 °C and slow-cool in furnace; no meaningful cold forming — heat treat is austenitize 1200–1230 °C (salt/vacuum), quench, then triple temper 540–560 °C 2 h each.
M30 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 | 0.75 – 0.85 | 0.8 |
| Mn | 0.15 – 0.4 | 0.28 |
| Si | 0.2 – 0.45 | 0.32 |
| Cr | 3.5 – 4.25 | 4 |
| Mo | 7.75 – 9 | 8.2 |
| W | 1.3 – 2.3 | 2 |
| V | 1 – 1.4 | 1.25 |
| Cored-hardness addition | 4.5 – 5.5 | 5 |
| P | ≤ 0.03 | |
| S | ≤ 0.03 | |
| Fe | balance |
What surface finishes work on M30?
Ferrous and non-stainless: finish with black oxide, steam treatment, nitriding or PVD TiN/TiCN/TiAlN coating; oil or VCI protection required in storage.
Surface treatments FabDigit runs on 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).
Organic Coating
Black / Phosphate
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Steel M30 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- T11330
How much does M30 cost?
M30 is a high-cost steel ($$$$), pricier than about 78% 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.
M30 — frequently asked
What is M30 used for?
M30 is typically used for heavy-duty lathe tools, milling cutters for hard materials and high-speed drilling. In short: cobalt red-hardness grade; 480 °C service rating; step up from M2.
What is the yield strength of M30?
M30 has a typical yield strength of 590 MPa (85.6 ksi) and a tensile strength of 900 MPa (131 ksi) — stronger than 76% of steel grades. Strength varies by condition: see the 5 listed tempers.
Is M30 easy to machine?
Not especially — machinability is rated fair (35/100, worse than 84% of steel grades). Machine only in the annealed condition with rigid setups, sharp carbide or coated-carbide tooling and generous coolant; after hardening only grinding (CBN/SG-alumina wheels) and EDM are practical.
Can M30 be welded?
Not readily — weldability is rated poor (15/100). Essentially not weldable structurally; repair only by TIG/laser with matched HSS filler at 480–540 °C preheat followed by immediate temper, otherwise quench cracking is likely.
What surface finishes work on M30?
Ferrous and non-stainless: finish with black oxide, steam treatment, nitriding or PVD TiN/TiCN/TiAlN coating; oil or VCI protection required in storage.
Can M30 be formed, bent or molded?
Hot forge 1050–1150 °C, stop above 900 °C and slow-cool in furnace; no meaningful cold forming — heat treat is austenitize 1200–1230 °C (salt/vacuum), quench, then triple temper 540–560 °C 2 h each.
What is the maximum service temperature of M30?
M30 is rated for continuous use to about 480°C (896 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between M30-ANN and M30 HT-64?
ANN is the default condition — standard as-supplied condition for machining tool blanks before hardening. HT-64: peak-hardness working condition for high-speed cutting tools where red hardness matters most. Yield strength is 590 MPa in ANN versus 1,900 MPa in HT-64.
How much does M30 cost?
M30 is a high-cost steel ($$$$), pricier than about 78% 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
- ASTM A600 — Standard Specification for Tool Steel High Speed — ASTM International (2016)
- ASM Handbook Vol. 1: Properties and Selection — Irons, Steels, and High-Performance Alloys — ASM International (1990)
- ASM Specialty Handbook: Tool Materials — ASM International (1995)
- ASM Handbook Vol. 16: Machining — ASM International (1989)
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.