Steel 4419H
Grade
AISI/SAE 4419 · UNS G44190
4419H = h-band hardenability-guaranteed grade
Order the H grade when Jominy end-quench hardenability limits must be certified for repeatable case/core response in heat treatment.
Values for the 4419H condition
Other 4419 tempers and conditions
4419 is listed in 8 conditions; see the grade overview at 4419.
Compare all 8 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Spheroidize annealed | Choose for cold forming/upsetting of fasteners and for the best tool life in heavy turning. | 300 | 470 | 30 | 135 HB | 8 % IACS |
ADefault Solution annealed | Standard stock condition for gear blanks and pins: softest, most machinable state prior to carburizing. | 330 | 500 | 25 | 145 HB | — |
4419HThis page H-band hardenability-guaranteed grade | Order the H grade when Jominy end-quench hardenability limits must be certified for repeatable case/core response in heat treatment. | 335 | 500 | 25 | 148 HB | 8 % IACS |
Hot rolled | Cheapest mill condition for parts that will be fully carburized and hardened after machining. | 350 | 540 | 23 | 160 HB | 8 % IACS |
Normalized | Use to homogenize forgings and refine grain before carburizing, giving more uniform case depth and less distortion. | 385 | 570 | 22 | 170 HB | 8 % IACS |
Cold drawn | Pick for close-tolerance, bright-finish bar where higher as-supplied strength and better chip control are wanted. | 500 | 600 | 14 | 180 HB | 8 % IACS |
direct quenched and tempered (core properties, ~30 HRC) | Use when the part is not carburized but needs a tough, medium-strength through-hardened body (small sections only). | 720 | 900 | 17 | 30 HRC | — |
Carburized and hardened | The service condition for gears, splines and pins: hard wear/pitting-resistant case with a tough ~25–35 HRC core. | 750 | 1,000 | 12 | 60 HRC | — |
What is 4419H?
4419H is 4419 in the 4419H grade — order the H grade when Jominy end-quench hardenability limits must be certified for repeatable case/core response in heat treatment. 4419H has a yield strength of 335 MPa (48.6 ksi) and a tensile strength of 500 MPa (72.5 ksi) — weaker than 77% of steel grades. Elongation at break is 25% and the elastic modulus is 205 GPa (29.7 Msi). 4419H has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,425°C (2,597 °F). A is the default condition FabDigit quotes; 4419H is available on request or by drawing note.
Advantages
- Low embodied carbon — 1.9 kg CO₂/kg, better than 92% of steel grades
- Ductile — tolerates forming and impact — 25%, better than 77% of steel grades
Limitations
- Low strength — 335 MPa (48.6 ksi), worse than 77% of steel grades
4419H properties
Typical room-temperature values for 4419H; 22 are specific to this condition. Other listed values are 4419 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
4419H has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,425°C (2,597 °F).
Mechanical13
4419H has a yield strength of 335 MPa (48.6 ksi) and a tensile strength of 500 MPa (72.5 ksi) — weaker than 77% of steel grades. Elongation at break is 25% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
4419H is rated for continuous service to 400°C (752 °F). It conducts heat at 42 W/m·K (24.3 BTU/hr·ft·°F), worse than 56% of steel grades. Thermal expansion is 12.2 µm/m·K (6.78 µin/in·°F).
Electrical3
4419H conducts electricity at 8 % IACS, better than 55% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (11/100), worse than 73% of steel grades.
Sustainability4
Producing a kilogram of 4419H takes about 25 MJ of energy and emits 1.9 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 30%.
Manufacturability7
4419H's machinability is good (58/100, better than 75% of steel grades); weldability good (62/100); formability good (58/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 4419H
Is 4419 easy to machine?
Machine in the annealed or normalized state (~65 % of 1212); sharp carbide or coated-carbide tools with flood coolant handle the gummy low-carbon chips, and all cutting must be finished before carburizing.
Can 4419 be welded?
Weldable with low-hydrogen consumables at ~150 °C preheat when in the soft condition; never weld after carburizing, and stress relieve/re-heat-treat welded assemblies before case hardening.
Can 4419 be formed, bent or molded?
Good cold and hot formability in the annealed/spheroidized state (forge 1150–1230 °C, finish above 900 °C); normalize after forging to refine grain for uniform case depth.
What surface finishes work on 4419?
No natural corrosion resistance — protect with oil, phosphate/black oxide, zinc or manganese phosphate; ground and superfinished case surfaces improve gear pitting life, and shot peening after carburizing raises bending fatigue.
4419 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 | 0.18 – 0.23 | 0.2 |
| Mn | 0.45 – 0.65 | 0.55 |
| Si | 0.15 – 0.35 | 0.25 |
| Mosole alloying addition; no Cr or Ni specified | 0.45 – 0.6 | 0.52 |
| P | ≤ 0.04 | — |
| S | ≤ 0.04 | — |
| Fe | balance | — |
4419H — frequently asked
What is 4419H used for?
4419H is typically used for carburized gears, pins, camshafts and case-hardened shafts. In short: mo-only carburizing steel; tough core after case hardening; no Cr or Ni content.
What is the yield strength of 4419H?
4419H has a typical yield strength of 335 MPa (48.6 ksi) and a tensile strength of 500 MPa (72.5 ksi) — weaker than 77% of steel grades. Strength varies by condition: see the 8 listed tempers.
Is 4419H easy to machine?
Reasonably — machinability is rated good (58/100, better than 75% of steel grades). Machine in the annealed or normalized state (~65 % of 1212); sharp carbide or coated-carbide tools with flood coolant handle the gummy low-carbon chips, and all cutting must be finished before carburizing.
Can 4419H be welded?
Yes — weldability is rated good (62/100). Weldable with low-hydrogen consumables at ~150 °C preheat when in the soft condition; never weld after carburizing, and stress relieve/re-heat-treat welded assemblies before case hardening.
What surface finishes work on 4419H?
No natural corrosion resistance — protect with oil, phosphate/black oxide, zinc or manganese phosphate; ground and superfinished case surfaces improve gear pitting life, and shot peening after carburizing raises bending fatigue.
Can 4419H be formed, bent or molded?
Good cold and hot formability in the annealed/spheroidized state (forge 1150–1230 °C, finish above 900 °C); normalize after forging to refine grain for uniform case depth.
What is the maximum service temperature of 4419H?
4419H 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 4419-A and 4419-CH?
A is the default condition — standard stock condition for gear blanks and pins: softest, most machinable state prior to carburizing. CH: the service condition for gears, splines and pins: hard wear/pitting-resistant case with a tough ~25–35 HRC core. Yield strength is 330 MPa in A versus 750 MPa in CH.
Sources
- SAE J404 — Chemical Compositions of SAE Alloy Steels — SAE International (2021)
- SAE J1268 — Hardenability Bands for Carbon and Alloy H Steels — SAE International (2019)
- ASTM A29/A29M — Steel Bars, Carbon and Alloy, Hot-Wrought, General Requirements — ASTM (2020)
- ASTM A322 — Steel Bars, Alloy, Standard Grades — ASTM (2020)
- ASM Handbook Vol.1: Properties and Selection — Irons, Steels, and High-Performance Alloys — ASM International (1990)
- ASM Handbook Vol.4: Heat Treating (carburizing of Mo carburizing steels) — ASM International (1991)
- Machining Data Handbook — Metcut Research Associates (1980)
- MMPDS-style typical low-alloy steel elastic and thermal data — Battelle/FAA (2021)
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.