Steel 38KhMYuA-A (Solution annealed)
Temper
EN 41CrAlMo7-10 · GB 38CrMoAlA
Softest supply condition for rough machining, deep drilling or cold work before quench-and-temper.
Values for the A condition
Other 38KhMYuA tempers and conditions
38KhMYuA is listed in 7 conditions; see the grade overview at 38KhMYuA.
Compare all 7 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
AThis page Solution annealed | Softest supply condition for rough machining, deep drilling or cold work before quench-and-temper. | 420 | 700 | 20 | 210 HB | — |
Hot rolled | Mill as-rolled bar for customers who will do their own full heat treatment; hardness variable and machining awkward. | 560 | 880 | 15 | 26 HRC | 6.6 % IACS |
Normalized | Grain refinement and structure homogenisation before final Q&T, or for lightly loaded parts. | 600 | 880 | 16 | 25 HRC | 6.6 % IACS |
Cold drawn | Bright bar with close diameter tolerance for small shafts and screws that will be nitrided after finish machining. | 620 | 800 | 12 | 22 HRC | 6.6 % IACS |
QT28-32Default Q&T 28–32 HRC | Standard commercial condition: tough, machinable core that is dimensionally stable for subsequent gas nitriding. | 860 | 1,000 | 16 | 30 HRC | — |
Q&T + Gas Nitrided | Final service condition: glass-hard, wear- and scuff-resistant surface with high fatigue strength on a tough Q&T core. | 860 | 1,000 | 14 | 67 HRC | — |
Q&T 32–36 HRC | Higher-strength core for heavily loaded shafts and screws where some toughness is traded for strength. | 980 | 1,130 | 13 | 34 HRC | — |
What is 38KhMYuA-A?
38KhMYuA-A is 38KhMYuA in the A temper — softest supply condition for rough machining, deep drilling or cold work before quench-and-temper. 38KhMYuA-A has a yield strength of 420 MPa (60.9 ksi) and a tensile strength of 700 MPa (102 ksi) — weaker than 53% of steel grades. Elongation at break is 20% and the elastic modulus is 210 GPa (30.5 Msi). 38KhMYuA-A has a density of 7.7 g/cm³ (0.278 lb/in³), lighter than 95% of steel grades. It melts at 1,420°C (2,588 °F). QT28-32 is the default condition FabDigit quotes; A is available on request or by drawing note.
Advantages
- High service temperature — 500°C (932 °F), better than 90% of steel grades
- Polishes to a fine finish — 65/100, better than 78% of steel grades
Limitations
- Poor heat conductor — 34 W/m·K (19.6 BTU/hr·ft·°F), worse than 77% of steel grades
- Difficult to weld — 25/100, worse than 77% of steel grades
- Low electrical conductivity — 6.6 % IACS, worse than 76% of steel grades
38KhMYuA-A properties
Typical room-temperature values for 38KhMYuA-A; 13 are specific to this condition. Other listed values are 38KhMYuA reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
38KhMYuA-A has a density of 7.7 g/cm³ (0.278 lb/in³), lighter than 95% of steel grades. It melts at 1,420°C (2,588 °F).
Mechanical16
38KhMYuA-A has a yield strength of 420 MPa (60.9 ksi) and a tensile strength of 700 MPa (102 ksi) — weaker than 53% of steel grades. Elongation at break is 20% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
38KhMYuA-A is rated for continuous service to 500°C (932 °F). It conducts heat at 34 W/m·K (19.6 BTU/hr·ft·°F), worse than 77% of steel grades. Thermal expansion is 11.8 µm/m·K (6.56 µin/in·°F).
Electrical3
38KhMYuA-A conducts electricity at 6.6 % IACS, worse than 76% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (13/100), better than 66% of steel grades.
Sustainability4
Producing a kilogram of 38KhMYuA-A takes about 32 MJ of energy and emits 2.3 kg of CO₂ — more than 70% of steel grades. Typical recycled content is 30%.
Manufacturability6
38KhMYuA-A's machinability is good (55/100, better than 62% of steel grades); weldability poor (25/100); formability fair (40/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 38KhMYuA-A
Is 38KhMYuA easy to machine?
Rough machine in the annealed state; finish machine after Q&T at 28–32 HRC with carbide tooling, then leave 0.05–0.10 mm grinding stock for post-nitriding finishing since the nitrided case is essentially unmachinable.
Can 38KhMYuA be welded?
Poor weldability — high hardenability plus ~1 % Al gives hard, crack-prone HAZ and oxide inclusions; if unavoidable use 250–350 °C preheat, low-hydrogen consumables and immediate stress relief/temper, and never weld a nitrided surface.
Can 38KhMYuA be formed, bent or molded?
Hot forge at 1150–850 °C followed by slow cooling and annealing; cold forming is not practical above the annealed condition.
What surface finishes work on 38KhMYuA?
Grind or lap after nitriding to restore tolerance; the white layer may be lightly removed; black oxide, phosphating or light oiling is used for rust protection — no anodizing applies.
38KhMYuA 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 | 0.35 – 0.42 | 0.38 |
| Si | 0.2 – 0.45 | 0.3 |
| Mn | 0.3 – 0.6 | 0.45 |
| Cr | 1.35 – 1.65 | 1.5 |
| Mo | 0.15 – 0.25 | 0.2 |
| Alforms hard AlN in the nitrided case | 0.7 – 1.1 | 0.9 |
| Niresidual | ≤ 0.3 | — |
| Curesidual | ≤ 0.3 | — |
| S | ≤ 0.03 | — |
| P | ≤ 0.03 | — |
| Fe | balance | — |
38KhMYuA-A — frequently asked
What is 38KhMYuA-A used for?
38KhMYuA-A is typically used for gears, shafts and pump and valve parts. In short: CIS-standard nitriding steel; equivalent to 41CrAlMo7-10; high-hardness nitrided case.
What is the yield strength of 38KhMYuA-A?
38KhMYuA-A has a typical yield strength of 420 MPa (60.9 ksi) and a tensile strength of 700 MPa (102 ksi) — weaker than 53% of steel grades. Strength varies by condition: see the 7 listed tempers.
Is 38KhMYuA-A easy to machine?
Reasonably — machinability is rated good (55/100, better than 62% of steel grades). Rough machine in the annealed state; finish machine after Q&T at 28–32 HRC with carbide tooling, then leave 0.05–0.10 mm grinding stock for post-nitriding finishing since the nitrided case is essentially unmachinable.
Can 38KhMYuA-A be welded?
Not readily — weldability is rated poor (25/100). Poor weldability — high hardenability plus ~1 % Al gives hard, crack-prone HAZ and oxide inclusions; if unavoidable use 250–350 °C preheat, low-hydrogen consumables and immediate stress relief/temper, and never weld a nitrided surface.
What surface finishes work on 38KhMYuA-A?
Grind or lap after nitriding to restore tolerance; the white layer may be lightly removed; black oxide, phosphating or light oiling is used for rust protection — no anodizing applies.
Can 38KhMYuA-A be formed, bent or molded?
Hot forge at 1150–850 °C followed by slow cooling and annealing; cold forming is not practical above the annealed condition.
What is the maximum service temperature of 38KhMYuA-A?
38KhMYuA-A is rated for continuous use to about 500°C (932 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 38KhMYuA QT28-32 and 38KhMYuA-A?
QT28-32 is the default condition — standard commercial condition: tough, machinable core that is dimensionally stable for subsequent gas nitriding. A: softest supply condition for rough machining, deep drilling or cold work before quench-and-temper. Yield strength is 860 MPa in QT28-32 versus 420 MPa in A.
Sources
- ГОСТ 4543 Прокат из легированной конструкционной стали (38Х2МЮА) — Gosstandart (2016)
- GB/T 3077 (38CrMoAlA) — SAC (2015)
- EN 10085 Nitriding steels (41CrAlMo7-10, 1.8509) — CEN (2001)
- ASM Handbook Vol. 4 — Heat Treating (Nitriding) — ASM International (1991)
- 38CrMoAlA — Mysteel / 1688 (2025)
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.