Steel M52-ANN (Annealed)
Heat-treated state · default condition
AISI/SAE M52 · UNS T11352
Standard supply condition for machining, forming and blank preparation before hardening.
Values for the ANN condition
Other M52 tempers and conditions
M52 is listed in 5 conditions; see the grade overview at M52.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
ANNDefaultThis page Annealed | Standard supply condition for machining, forming and blank preparation before hardening. | 520 | 860 | 15 | 24 HRC | — |
Annealed, cold drawn / ground bar | Use when close diameter tolerance and good surface are needed on blanks before hardening. | 650 | 950 | 10 | 26 HRC | 3.1 % IACS |
Hardened & tempered 60–62 HRC | Choose when impact or shock loading matters more than maximum wear life (punches, shafts, heavily loaded rings). | 2,050 | 2,400 | 1 | 61 HRC | — |
Hardened + deep cryogenic (−196 °C) + triple temper, 65–66 HRC | Pick for premium bearing rings/balls where retained austenite must be minimised for dimensional stability and maximum wear life. | 2,100 | 2,300 | 0.5 | 66 HRC | 2.9 % IACS |
Hardened & tempered 63–65 HRC | Standard austenitize (~1190–1215 °C salt/vacuum), quench and triple temper at 540–560 °C for tools and premium bearing components. | 2,200 | 2,600 | 0.5 | 64 HRC | 23 W/m·K |
What is M52-ANN?
M52-ANN is M52 heat treated to ANN — standard supply condition for machining, forming and blank preparation before hardening. M52-ANN has a yield strength of 520 MPa (75.4 ksi) and a tensile strength of 860 MPa (125 ksi) — stronger than 67% of steel grades. Elongation at break is 15% and the elastic modulus is 213 GPa (30.9 Msi). M52-ANN has a density of 8.03 g/cm³ (0.29 lb/in³), heavier than 96% of steel grades. It melts at 1,240°C (2,264 °F).
Advantages
- Polishes to a fine finish — 80/100, better than 97% of steel grades
Limitations
- High embodied carbon — 3.3 kg CO₂/kg, worse than 92% of steel grades
- Difficult to weld — 15/100, worse than 91% of steel grades
- Low fracture toughness — 45 MPa·√m (41 ksi·√in), worse than 90% of steel grades
- Poor heat conductor — 24 W/m·K (13.9 BTU/hr·ft·°F), worse than 90% of steel grades
- Low electrical conductivity — 3.1 % IACS, worse than 89% of steel grades
M52-ANN properties
Typical room-temperature values for M52-ANN; 19 are specific to this condition. Other listed values are M52 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
M52-ANN has a density of 8.03 g/cm³ (0.29 lb/in³), heavier than 96% of steel grades. It melts at 1,240°C (2,264 °F).
Mechanical17
M52-ANN has a yield strength of 520 MPa (75.4 ksi) and a tensile strength of 860 MPa (125 ksi) — stronger than 67% of steel grades. Elongation at break is 15% and the elastic modulus is 213 GPa (30.9 Msi).
Thermal6
M52-ANN is rated for continuous service to 400°C (752 °F). It conducts heat at 24 W/m·K (13.9 BTU/hr·ft·°F), worse than 90% of steel grades. Thermal expansion is 11.2 µm/m·K (6.22 µin/in·°F).
Electrical3
M52-ANN conducts electricity at 3.1 % IACS, worse than 89% of steel grades.
Chemical & Environmental3
Corrosion resistance is poor (20/100), better than 87% of steel grades.
Sustainability4
Producing a kilogram of M52-ANN takes about 46 MJ of energy and emits 3.3 kg of CO₂ — more than 93% of steel grades. Typical recycled content is 40%.
Manufacturability7
M52-ANN's machinability is fair (40/100, worse than 77% of steel grades); weldability poor (15/100); formability poor (20/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with M52-ANN
Is M52 easy to machine?
Machine only in the annealed condition with rigid setups, cobalt HSS or coated carbide, low speeds and flood coolant; hardened parts require CBN grinding or EDM.
Can M52 be welded?
Not recommended for structural joints; repair welds only with matched HSS filler, 500–550 °C preheat and immediate temper to avoid quench cracking.
Can M52 be formed, bent or molded?
Hot work at 1050–1150 °C with slow controlled cooling and full spheroidize anneal; essentially no cold formability.
What surface finishes work on M52?
Grind and lap for bearing surfaces; protect with black oxide, phosphate or PVD TiN/TiAlN — the 4 % Cr does not give stainless behaviour.
M52 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 | 0.85 – 0.95 | 0.9 |
| Mn | 0.15 – 0.45 | 0.3 |
| Si | 0.2 – 0.45 | 0.3 |
| Cr | 3.5 – 4.3 | 3.9 |
| Mo | 4 – 4.9 | 4.5 |
| W | 0.75 – 1.5 | 1.1 |
| V | 1.65 – 2.25 | 2 |
| P | ≤ 0.03 | — |
| S | ≤ 0.03 | — |
| Fe | balance | — |
M52-ANN — frequently asked
What is M52-ANN used for?
M52-ANN is typically used for high-performance rolling bearings, cutting tools for abrasive materials and aerospace bearing components. In short: bearing-grade high-speed steel; higher C and V than M50; best machinability in group.
What is the yield strength of M52-ANN?
M52-ANN has a typical yield strength of 520 MPa (75.4 ksi) and a tensile strength of 860 MPa (125 ksi) — stronger than 67% of steel grades. Strength varies by condition: see the 5 listed tempers.
Is M52-ANN easy to machine?
Not especially — machinability is rated fair (40/100, worse than 77% of steel grades). Machine only in the annealed condition with rigid setups, cobalt HSS or coated carbide, low speeds and flood coolant; hardened parts require CBN grinding or EDM.
Can M52-ANN be welded?
Not readily — weldability is rated poor (15/100). Not recommended for structural joints; repair welds only with matched HSS filler, 500–550 °C preheat and immediate temper to avoid quench cracking.
What surface finishes work on M52-ANN?
Grind and lap for bearing surfaces; protect with black oxide, phosphate or PVD TiN/TiAlN — the 4 % Cr does not give stainless behaviour.
Can M52-ANN be formed, bent or molded?
Hot work at 1050–1150 °C with slow controlled cooling and full spheroidize anneal; essentially no cold formability.
What is the maximum service temperature of M52-ANN?
M52-ANN 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 M52-ANN and M52 HT-CRYO?
ANN is the default condition — standard supply condition for machining, forming and blank preparation before hardening. HT-CRYO: pick for premium bearing rings/balls where retained austenite must be minimised for dimensional stability and maximum wear life. Yield strength is 520 MPa in ANN versus 2,100 MPa in HT-CRYO.
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 (High-Speed Tool Steels) — 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. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.