Steel 1126 QT-24-28HRC
Hardness band
AISI/SAE 1126 · UNS G11260
Pick for higher-strength studs, pins and hydraulic parts still machinable after heat treatment.
Values for the QT-24-28HRC condition
Other 1126 tempers and conditions
1126 is listed in 9 conditions; see the grade overview at 1126.
Compare all 9 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
full anneal, softest bar condition | Pick when maximum softness/ductility is needed before heavy cold forming or deep boring. | 250 | 460 | 26 | 131 HB | — |
Hot rolled | Lowest-cost condition for larger diameters and parts that are fully machined or later heat treated. | 280 | 505 | 22 | 143 HB | 10 % IACS |
Normalized | Use to homogenize forged or heavy hot-rolled sections and give uniform, moderately strong structure before machining. | 310 | 545 | 22 | 156 HB | 10 % IACS |
Cold Drawn, Stress Relieved | Choose when machining-induced distortion must be minimized on long or asymmetric parts. | 460 | 565 | 15 | 163 HB | 10 % IACS |
Q&T | General-purpose quench-and-temper condition for shafts and couplings needing tougher, uniform medium strength. | 480 | 690 | 20 | 15 HRC | 10 % IACS |
CDDefault Cold drawn | Default stocked screw-machine bar: good size tolerance, straightness, surface finish and the best strength/machinability balance. | 505 | 585 | 12 | 170 HB | — |
Induction hardened | Use for wear surfaces on shafts and pins where a hard skin over a tough machinable core is wanted. | 520 | 620 | 11 | 45 HRC | 10 % IACS |
QT-24-28HRCThis page water quenched, tempered ~540 °C | Pick for higher-strength studs, pins and hydraulic parts still machinable after heat treatment. | 620 | 830 | 16 | 26 HRC | 10 % IACS |
water quenched, tempered ~450–480 °C (small sections) | Maximum practical through-hardened strength for thin bar; toughness and transverse ductility drop sharply. | 790 | 1,000 | 12 | 32 HRC | 10 % IACS |
What is 1126 QT-24-28HRC?
1126 QT-24-28HRC is 1126 heat treated to QT-24-28HRC — pick for higher-strength studs, pins and hydraulic parts still machinable after heat treatment. 1126 QT-24-28HRC has a yield strength of 620 MPa (89.9 ksi) and a tensile strength of 830 MPa (120 ksi) — stronger than 78% of steel grades. Elongation at break is 16% and the elastic modulus is 205 GPa (29.7 Msi). 1126 QT-24-28HRC has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,420°C (2,588 °F). CD is the default condition FabDigit quotes; QT-24-28HRC is available on request or by drawing note.
Advantages
- High electrical conductivity — 10 % IACS, better than 83% of steel grades
- High strength — 620 MPa (89.9 ksi), better than 78% of steel grades
Limitations
- Difficult to weld — 22/100, worse than 81% of steel grades
1126 QT-24-28HRC properties
Typical room-temperature values for 1126 QT-24-28HRC; 22 are specific to this condition. Other listed values are 1126 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
1126 QT-24-28HRC has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,420°C (2,588 °F).
Mechanical13
1126 QT-24-28HRC has a yield strength of 620 MPa (89.9 ksi) and a tensile strength of 830 MPa (120 ksi) — stronger than 78% of steel grades. Elongation at break is 16% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
1126 QT-24-28HRC is rated for continuous service to 425°C (797 °F). It conducts heat at 47 W/m·K (27.2 BTU/hr·ft·°F), better than 75% of steel grades. Thermal expansion is 11.7 µm/m·K (6.5 µin/in·°F).
Electrical3
1126 QT-24-28HRC conducts electricity at 10 % IACS, better than 83% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (11/100), worse than 73% of steel grades.
Sustainability4
Producing a kilogram of 1126 QT-24-28HRC takes about 25 MJ of energy and emits 2 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 35%.
Manufacturability7
1126 QT-24-28HRC's machinability is good (60/100, better than 83% of steel grades); weldability poor (22/100); formability poor (25/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 1126 QT-24-28HRC
Is 1126 easy to machine?
Excellent free-cutting behaviour — run high speeds with carbide, use positive rake and adequate coolant; MnS gives short chips and clean threads, ~78 % of 1212.
Can 1126 be welded?
Not recommended for structural welding; sulfur promotes hot cracking and porosity — if unavoidable, preheat 150–260 °C, low-hydrogen filler and post-weld stress relief.
Can 1126 be formed, bent or molded?
Limited cold forming (bending, light heading) in annealed/hot-rolled temper; avoid tight transverse bends because MnS stringers cause splitting. Hot forge 1100–1200 °C, never below ~900 °C.
What surface finishes work on 1126?
No anodizing (ferrous): use zinc/zinc-nickel plating, black oxide, manganese phosphate or paint; degrease well since sulfide inclusions can bleed and stain plated surfaces.
1126 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 grade G11260 | 0.23 – 0.29 | 0.26 |
| Mn | 0.7 – 1 | 0.85 |
| Sresulfurized for free machining (MnS inclusions) | 0.08 – 0.13 | 0.1 |
| P | ≤ 0.04 | 0.02 |
| Sinot specified for resulfurized bar; typical mill practice 0.15–0.30 | ≈ 0.2 | 0.2 |
| Fe | balance | — |
1126 QT-24-28HRC — frequently asked
What is 1126 QT-24-28HRC used for?
1126 QT-24-28HRC is typically used for shafts, studs and structural fasteners. In short: heat-treatable free-machining bar; stronger than 1117/1119; not for structural welds.
What is the yield strength of 1126 QT-24-28HRC?
1126 QT-24-28HRC has a typical yield strength of 620 MPa (89.9 ksi) and a tensile strength of 830 MPa (120 ksi) — stronger than 78% of steel grades. Strength varies by condition: see the 9 listed tempers.
Is 1126 QT-24-28HRC easy to machine?
Reasonably — machinability is rated good (60/100, better than 83% of steel grades). Excellent free-cutting behaviour — run high speeds with carbide, use positive rake and adequate coolant; MnS gives short chips and clean threads, ~78 % of 1212.
Can 1126 QT-24-28HRC be welded?
Not readily — weldability is rated poor (22/100). Not recommended for structural welding; sulfur promotes hot cracking and porosity — if unavoidable, preheat 150–260 °C, low-hydrogen filler and post-weld stress relief.
What surface finishes work on 1126 QT-24-28HRC?
No anodizing (ferrous): use zinc/zinc-nickel plating, black oxide, manganese phosphate or paint; degrease well since sulfide inclusions can bleed and stain plated surfaces.
Can 1126 QT-24-28HRC be formed, bent or molded?
Limited cold forming (bending, light heading) in annealed/hot-rolled temper; avoid tight transverse bends because MnS stringers cause splitting. Hot forge 1100–1200 °C, never below ~900 °C.
What is the maximum service temperature of 1126 QT-24-28HRC?
1126 QT-24-28HRC is rated for continuous use to about 425°C (797 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 1126-CD and 1126-HR?
CD is the default condition — default stocked screw-machine bar: good size tolerance, straightness, surface finish and the best strength/machinability balance. HR: lowest-cost condition for larger diameters and parts that are fully machined or later heat treated. Yield strength is 505 MPa in CD versus 280 MPa in HR.
Sources
- SAE J403 — Chemical Compositions of SAE Carbon Steels — SAE International (2014)
- ASTM A29/A29M — General Requirements for Steel Bars, Carbon and Alloy, Hot-Wrought — 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)
- ASM Handbook Vol.16 — Machining — ASM International (1989)
- GB/T 8731 (comparable Y30 grade) — SAC (China) (2008)
- Mysteel / 1688 free-machining bar spot quotations (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.