Steel Y12
GB Y12
Y12 is a low-carbon resulfurized free-cutting steel to GB/T 8731, directly comparable to AISI 1212 for general automatic-lathe work.
Reference datasheet — Y12 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the CD condition
Y12 tempers and conditions
Y12 is supplied in 6 conditions, soft to hard. CD is the default FabDigit quotes; the values on this page are for it.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Solution annealed | Use before severe cold forming, heading or when maximum ductility is needed; machining finish is poorer (gummy). | 230 | 400 | 30 | 115 HB | 11 % IACS |
Hot rolled | Cheapest form; pick for larger-diameter bar that will be fully machined or subsequently cold drawn. | 260 | 450 | 26 | 130 HB | — |
Normalized | Pick to homogenise structure and improve toughness of hot-rolled bar before finish machining. | 270 | 440 | 28 | 130 HB | 10.5 % IACS |
Carburized and hardened | Select when a machined free-cutting part needs a wear-resistant case (pins, small shafts, bushings); core stays soft and low strength. | 400 | 600 | 12 | 58 HRC | — |
Cold Drawn + Stress Relieved | Choose when long slender turned parts must stay straight after heavy one-side machining. | 420 | 560 | 13 | 170 HB | 10.5 % IACS |
CDDefault Cold drawn | Standard stock condition: bright, close-tolerance bar with the best surface finish and chip control on multi-spindle automatics. | 450 | 590 | 10 | 180 HB | — |
What is Y12?
Y12 is a low-carbon resulfurized free-cutting steel to GB/T 8731, directly comparable to AISI 1212 for general automatic-lathe work. It is supplied as bar for high-volume turned parts, with default properties of about 450 MPa yield, 590 MPa tensile, 10 % elongation, 180 HB (89 HRB) and a machinability score of 85; conditions on file include hot-rolled, cold-drawn, stress-relieved, annealed, normalized and cold-heading quality. High sulfur and phosphorus rule out structural welding, cold forming is limited to light bends (score 30), and bare bar rusts without plating. 12L14 cuts faster where lead is acceptable. Y12 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,495°C (2,723 °F). Y12 has a yield strength of 450 MPa (65.3 ksi) and a tensile strength of 590 MPa (85.6 ksi) — stronger than 52% of steel grades. Elongation at break is 10% and the elastic modulus is 200 GPa (29 Msi).
What is Y12 used for?
- Screw machine parts
- Small shafts
- Fittings
Advantages
- Easy to machine — 85/100, better than 98% of steel grades
- Conducts heat well — 51 W/m·K (29.5 BTU/hr·ft·°F), better than 92% of steel grades
- High electrical conductivity — 10.5 % IACS, better than 89% of steel grades
Limitations
- Limited ductility — 10%, worse than 91% of steel grades
- Hard to polish — 45/100, worse than 84% of steel grades
- Difficult to weld — 25/100, worse than 77% of steel grades
Y12 properties
Typical room-temperature values for Y12-CD; bars are the position among steel grades.
Physical3
Y12 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,495°C (2,723 °F).
Mechanical14
Y12 has a yield strength of 450 MPa (65.3 ksi) and a tensile strength of 590 MPa (85.6 ksi) — stronger than 52% of steel grades. Elongation at break is 10% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
Y12 is rated for continuous service to 350°C (662 °F). It conducts heat at 51 W/m·K (29.5 BTU/hr·ft·°F), better than 92% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
Y12 conducts electricity at 10.5 % IACS, better than 89% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (8/100), worse than 99% of steel grades.
Sustainability4
Producing a kilogram of Y12 takes about 25 MJ of energy and emits 2 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 30%.
Manufacturability7
Y12's machinability is excellent (85/100, better than 98% of steel grades); weldability poor (25/100); formability poor (30/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the steel family
Yield strength against density for every steel grade FabDigit runs. Y12 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with Y12
Is Y12 easy to machine?
The benchmark free-cutting steel (100 % rating): run high speeds with light feeds, gives short broken chips and bright finish; keep tool nose sharp to avoid smearing the soft ferrite.
Can Y12 be welded?
Not recommended for structural welds — high S and P cause hot cracking and porosity; if unavoidable use low-hydrogen filler, preheat and minimum restraint.
Can Y12 be formed, bent or molded?
Only light cold bending in the rolling direction; transverse bends and cold heading split along sulphide stringers, so anneal or choose a killed low-C grade instead.
Y12 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 | 0.08 – 0.16 | 0.12 |
| Si | 0.15 – 0.35 | 0.25 |
| Mncombines with S to form free-cutting MnS | 0.7 – 1 | 0.85 |
| Sintentional — chip breaker | 0.1 – 0.2 | 0.15 |
| Pintentional — improves surface finish, embrittles ferrite | 0.08 – 0.15 | 0.11 |
| Crresidual | ≤ 0.1 | |
| Niresidual | ≤ 0.2 | |
| Curesidual | ≤ 0.2 | |
| Fe | balance |
What surface finishes work on Y12?
Takes zinc/nickel plating, black oxide and phosphate well after degreasing; polished surfaces can show inclusion pits, and bare bar must be oiled to prevent rust.
Surface treatments FabDigit runs on steel parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Organic Coating
Black / Phosphate
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Steel Y12 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- Similar grades
- 1212
How much does Y12 cost?
Y12 is a budget-cost steel ($), cheaper than about 90% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Y12 — frequently asked
What is Y12 used for?
Y12 is typically used for screw machine parts, small shafts and fittings. In short: 1212-equivalent free-cutting bar; low-carbon screw stock; not for welded assemblies.
What is the yield strength of Y12?
Y12 has a typical yield strength of 450 MPa (65.3 ksi) and a tensile strength of 590 MPa (85.6 ksi) — stronger than 52% of steel grades. Strength varies by condition: see the 6 listed tempers.
Is Y12 easy to machine?
Yes — machinability is rated excellent (85/100, better than 98% of steel grades). The benchmark free-cutting steel (100 % rating): run high speeds with light feeds, gives short broken chips and bright finish; keep tool nose sharp to avoid smearing the soft ferrite.
Can Y12 be welded?
Not readily — weldability is rated poor (25/100). Not recommended for structural welds — high S and P cause hot cracking and porosity; if unavoidable use low-hydrogen filler, preheat and minimum restraint.
What surface finishes work on Y12?
Takes zinc/nickel plating, black oxide and phosphate well after degreasing; polished surfaces can show inclusion pits, and bare bar must be oiled to prevent rust.
Can Y12 be formed, bent or molded?
Only light cold bending in the rolling direction; transverse bends and cold heading split along sulphide stringers, so anneal or choose a killed low-C grade instead.
What is the maximum service temperature of Y12?
Y12 is rated for continuous use to about 350°C (662 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between Y12-CD and Y12-A?
CD is the default condition — standard stock condition: bright, close-tolerance bar with the best surface finish and chip control on multi-spindle automatics. A: use before severe cold forming, heading or when maximum ductility is needed; machining finish is poorer (gummy). Yield strength is 450 MPa in CD versus 230 MPa in A.
How much does Y12 cost?
Y12 is a budget-cost steel ($), cheaper than about 90% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- GB/T 699 / ASTM A108 & SAE J403 (1212 comparison) — SAC / ASTM / SAE (2018)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels — ASM International (1990)
- ASM Handbook Vol.16 — Machining — ASM International (1989)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.