Steel 1019 CARB-QT
Heat-treated state
AISI/SAE 1019 · UNS G10190
CARB-QT = carburized, Quenched & Tempered
Pick for gears, pins and bushings needing a hard wear surface over a tough, ductile low-carbon core.
Values for the CARB-QT condition
Other 1019 tempers and conditions
1019 is listed in 6 conditions; see the grade overview at 1019.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Hot rolled | Lowest-cost condition for welded structures and parts that will be machined all over or later heat treated. | 225 | 407 | 25 | 116 HB | — |
Normalized | Use to refine grain and homogenize forgings or weldments before machining or carburizing. | 250 | 430 | 30 | 121 HB | — |
Solution annealed | Softest condition, chosen for maximum cold formability (deep drawing, cold heading) or to soften after cold work. | 260 | 385 | 34 | 111 HB | — |
Cold Drawn, Stress Relieved | Choose when machined parts must stay straight — residual drawing stresses are removed at ~550–650 °C with only slight strength loss. | 360 | 450 | 18 | 126 HB | 10.8 % IACS |
CDDefault Cold drawn | Standard stock condition: higher strength, close size tolerance and bright surface for shafts, pins and screw-machine parts. | 395 | 470 | 15 | 131 HB | — |
CARB-QTThis page Carburized, Quenched & Tempered | Pick for gears, pins and bushings needing a hard wear surface over a tough, ductile low-carbon core. | 430 | 640 | 15 | 60 HRC | — |
What is 1019 CARB-QT?
1019 CARB-QT is 1019 heat treated to CARB-QT — pick for gears, pins and bushings needing a hard wear surface over a tough, ductile low-carbon core. 1019 CARB-QT has a yield strength of 430 MPa (62.4 ksi) and a tensile strength of 640 MPa (92.8 ksi) — weaker than 51% of steel grades. Elongation at break is 15% and the elastic modulus is 205 GPa (29.7 Msi). 1019 CARB-QT has a density of 7.87 g/cm³ (0.284 lb/in³), heavier than 92% of steel grades. It melts at 1,425°C (2,597 °F). CD is the default condition FabDigit quotes; CARB-QT is available on request or by drawing note.
Advantages
- Conducts heat well — 51.9 W/m·K (30 BTU/hr·ft·°F), better than 96% of steel grades
- High electrical conductivity — 10.8 % IACS, better than 94% of steel grades
Limitations
- Limited service temperature — 180°C (356 °F), worse than 98% of steel grades
- Difficult to machine — 18/100, worse than 97% of steel grades
- Limited formability — 10/100, worse than 95% of steel grades
1019 CARB-QT properties
Typical room-temperature values for 1019 CARB-QT; 12 are specific to this condition. Other listed values are 1019 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
1019 CARB-QT has a density of 7.87 g/cm³ (0.284 lb/in³), heavier than 92% of steel grades. It melts at 1,425°C (2,597 °F).
Mechanical16
1019 CARB-QT has a yield strength of 430 MPa (62.4 ksi) and a tensile strength of 640 MPa (92.8 ksi) — weaker than 51% of steel grades. Elongation at break is 15% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
1019 CARB-QT is rated for continuous service to 180°C (356 °F). It conducts heat at 51.9 W/m·K (30 BTU/hr·ft·°F), better than 96% of steel grades. Thermal expansion is 11.7 µm/m·K (6.5 µin/in·°F).
Electrical3
1019 CARB-QT conducts electricity at 10.8 % IACS, better than 94% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (10/100), worse than 86% of steel grades.
Sustainability4
Producing a kilogram of 1019 CARB-QT takes about 25 MJ of energy and emits 2 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 30%.
Manufacturability8
1019 CARB-QT's machinability is poor (18/100, worse than 97% of steel grades); weldability poor (30/100); formability not recommended (10/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 1019 CARB-QT
Is 1019 easy to machine?
Gummy in the annealed/hot-rolled state — prefer cold drawn, sharp positive-rake tools, high speed and good coolant to avoid built-up edge; consider 1117/12L14 if chips are a problem.
Can 1019 be welded?
Excellent by all arc, resistance and oxyfuel processes with ER70S-x/E70xx filler; no preheat needed under ~25 mm section.
Can 1019 be formed, bent or molded?
Very good cold bending, roll forming, stamping and cold heading; anneal or use hot rolled stock for severe draws.
What surface finishes work on 1019?
No natural corrosion resistance — specify zinc or nickel plating, phosphate + oil, black oxide or paint; case hardening also improves wear.
1019 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 |
|---|---|---|
| CSAE J403 / ASTM A29 | 0.15 – 0.2 | 0.18 |
| Mn | 0.7 – 1 | 0.85 |
| P | ≤ 0.04 | 0.02 |
| S | ≤ 0.05 | 0.03 |
| Fe | balance | — |
1019 CARB-QT — frequently asked
What is 1019 CARB-QT used for?
1019 CARB-QT is typically used for machine parts, carburized gears, shafts, structural brackets and cold-formed components. In short: highly weldable low-carbon bar; slightly stronger than 1018; low-cost carburizing grade.
What is the yield strength of 1019 CARB-QT?
1019 CARB-QT has a typical yield strength of 430 MPa (62.4 ksi) and a tensile strength of 640 MPa (92.8 ksi) — weaker than 51% of steel grades. Strength varies by condition: see the 6 listed tempers.
Is 1019 CARB-QT easy to machine?
Not especially — machinability is rated poor (18/100, worse than 97% of steel grades). Gummy in the annealed/hot-rolled state — prefer cold drawn, sharp positive-rake tools, high speed and good coolant to avoid built-up edge; consider 1117/12L14 if chips are a problem.
Can 1019 CARB-QT be welded?
Not readily — weldability is rated poor (30/100). Excellent by all arc, resistance and oxyfuel processes with ER70S-x/E70xx filler; no preheat needed under ~25 mm section.
What surface finishes work on 1019 CARB-QT?
No natural corrosion resistance — specify zinc or nickel plating, phosphate + oil, black oxide or paint; case hardening also improves wear.
Can 1019 CARB-QT be formed, bent or molded?
Very good cold bending, roll forming, stamping and cold heading; anneal or use hot rolled stock for severe draws.
What is the maximum service temperature of 1019 CARB-QT?
1019 CARB-QT is rated for continuous use to about 180°C (356 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 1019-CD and 1019-HR?
CD is the default condition — standard stock condition: higher strength, close size tolerance and bright surface for shafts, pins and screw-machine parts. HR: lowest-cost condition for welded structures and parts that will be machined all over or later heat treated. Yield strength is 395 MPa in CD versus 225 MPa in HR.
Sources
- SAE J403 — Chemical Compositions of SAE Carbon Steels — SAE International (2014)
- ASTM A29/A29M — Steel Bars, Carbon and Alloy, Hot-Wrought, General Requirements — ASTM (2020)
- ASTM A108 — Steel Bar, Carbon and Alloy, Cold-Finished — ASTM (2018)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- Machinery's Handbook, 31st ed. (machinability ratings) — Industrial Press (2020)
- Mysteel / 1688 — Mysteel (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.