Steel SUM22 CH-Q
Heat-treated state
JIS SUM22
CH-Q = carburized, quenched and tempered
Chosen for machined parts needing a wear-resistant surface (pins, small shafts) while keeping a tough low-carbon core.
Values for the CH-Q condition
Other SUM22 tempers and conditions
SUM22 is listed in 5 conditions; see the grade overview at SUM22.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Solution annealed | Softest condition, chosen ahead of cold heading, thread rolling, staking or deep form operations. | 230 | 400 | 28 | 115 HB | — |
Hot rolled | Cheapest form for large-diameter stock or parts that will be fully machined; lowest strength, roughest surface. | 250 | 415 | 25 | 121 HB | — |
Cold drawn, stress relieved | Pick when slender or asymmetrically machined parts must stay straight after material removal. | 380 | 510 | 14 | 150 HB | 10 % IACS |
CDDefault Cold drawn | The standard stock condition for automatic-lathe work: tight tolerance, straight, high hardness for good chip control and finish. | 415 | 540 | 10 | 163 HB | — |
CH-QThis page Carburized, quenched and tempered | Chosen for machined parts needing a wear-resistant surface (pins, small shafts) while keeping a tough low-carbon core. | 420 | 620 | 10 | 58 HRC | 9 % IACS |
What is SUM22 CH-Q?
SUM22 CH-Q is SUM22 heat treated to CH-Q — chosen for machined parts needing a wear-resistant surface (pins, small shafts) while keeping a tough low-carbon core. SUM22 CH-Q has a yield strength of 420 MPa (60.9 ksi) and a tensile strength of 620 MPa (89.9 ksi) — weaker than 53% of steel grades. Elongation at break is 10% and the elastic modulus is 205 GPa (29.7 Msi). SUM22 CH-Q 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; CH-Q is available on request or by drawing note.
Advantages
- Low embodied carbon — 1.9 kg CO₂/kg, better than 92% of steel grades
- Conducts heat well — 49 W/m·K (28.3 BTU/hr·ft·°F), better than 83% of steel grades
Limitations
- Difficult to weld — 10/100, worse than 99% of steel grades
- Limited formability — 5/100, worse than 99% of steel grades
- Limited service temperature — 180°C (356 °F), worse than 98% of steel grades
- Difficult to machine — 25/100, worse than 93% of steel grades
- Limited ductility — 10%, worse than 91% of steel grades
SUM22 CH-Q properties
Typical room-temperature values for SUM22 CH-Q; 23 are specific to this condition. Other listed values are SUM22 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
SUM22 CH-Q 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).
Mechanical13
SUM22 CH-Q has a yield strength of 420 MPa (60.9 ksi) and a tensile strength of 620 MPa (89.9 ksi) — weaker than 53% of steel grades. Elongation at break is 10% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
SUM22 CH-Q is rated for continuous service to 180°C (356 °F). It conducts heat at 49 W/m·K (28.3 BTU/hr·ft·°F), better than 83% of steel grades. Thermal expansion is 11.9 µm/m·K (6.61 µin/in·°F).
Electrical3
SUM22 CH-Q conducts electricity at 9 % IACS, better than 71% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (8/100), worse than 99% of steel grades.
Sustainability4
Producing a kilogram of SUM22 CH-Q takes about 25 MJ of energy and emits 1.9 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 35%.
Manufacturability7
SUM22 CH-Q's machinability is poor (25/100, worse than 93% of steel grades); weldability not recommended (10/100); formability not recommended (5/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with SUM22 CH-Q
Is SUM22 easy to machine?
Outstanding on multi-spindle and Swiss lathes — high speeds, short broken chips and bright finishes; keep feed high enough to stay above the built-up-edge range and use sulfurized or neat cutting oil.
Can SUM22 be welded?
Not recommended for structural welds: high sulfur causes hot cracking and porosity; if unavoidable use low-hydrogen filler, preheat and expect reduced joint properties.
Can SUM22 be formed, bent or molded?
Only mild cold bending/thread rolling in the annealed state; sulfide stringers make transverse bends and cold heading crack-prone.
What surface finishes work on SUM22?
Take plating (zinc, Zn-Ni, electroless nickel), black oxide or phosphate readily; degrease well since inclusions can trap electrolyte and cause staining — no anodizing.
SUM22 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 |
|---|---|---|
| CJIS G 4804 max only | ≤ 0.13 | 0.1 |
| Mncombines with S as MnS chip breakers | 0.7 – 1 | 0.85 |
| PAISI 1213 permits 0.07–0.12 P for extra machinability | ≤ 0.04 | 0.03 |
| Sresulfurized free-machining addition | 0.24 – 0.33 | 0.28 |
| Sinot specified in JIS; kept low in rimmed/killed practice | ≤ 0.1 | — |
| Curesidual limit | ≤ 0.3 | — |
| Fe | balance | — |
SUM22 CH-Q — frequently asked
What is SUM22 CH-Q used for?
SUM22 CH-Q is typically used for screw machine parts, bushings and small fittings. In short: highest machinability, score 92; benchmark automatic-lathe bar; low strength, not for welding.
What is the yield strength of SUM22 CH-Q?
SUM22 CH-Q has a typical yield strength of 420 MPa (60.9 ksi) and a tensile strength of 620 MPa (89.9 ksi) — weaker than 53% of steel grades. Strength varies by condition: see the 5 listed tempers.
Is SUM22 CH-Q easy to machine?
Not especially — machinability is rated poor (25/100, worse than 93% of steel grades). Outstanding on multi-spindle and Swiss lathes — high speeds, short broken chips and bright finishes; keep feed high enough to stay above the built-up-edge range and use sulfurized or neat cutting oil.
Can SUM22 CH-Q be welded?
Not readily — weldability is rated not recommended (10/100). Not recommended for structural welds: high sulfur causes hot cracking and porosity; if unavoidable use low-hydrogen filler, preheat and expect reduced joint properties.
What surface finishes work on SUM22 CH-Q?
Take plating (zinc, Zn-Ni, electroless nickel), black oxide or phosphate readily; degrease well since inclusions can trap electrolyte and cause staining — no anodizing.
Can SUM22 CH-Q be formed, bent or molded?
Only mild cold bending/thread rolling in the annealed state; sulfide stringers make transverse bends and cold heading crack-prone.
What is the maximum service temperature of SUM22 CH-Q?
SUM22 CH-Q 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 SUM22-CD and SUM22-A?
CD is the default condition — the standard stock condition for automatic-lathe work: tight tolerance, straight, high hardness for good chip control and finish. A: softest condition, chosen ahead of cold heading, thread rolling, staking or deep form operations. Yield strength is 415 MPa in CD versus 230 MPa in A.
Sources
- JIS G 4804 — Sulfur and sulfur-composition free-cutting steels — Japanese Standards Association (2019)
- SAE J403 / ASTM A108 — carbon steel chemical compositions (1213) — SAE / ASTM (2018)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels — ASM International (1990)
- ASM Handbook Vol.16 — Machining — ASM International (1989)
- Chinese equivalent grade tables Y12/Y15 vs SUM22 (GB/T 8731) — SAC (2008)
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.