Y20
Data verifiedY20 moves China’s free-cutting family (GB/T 8731) to a 0.20% carbon base with sulfur-only chip-breaking (no phosphorus boost), trading a little machinability against the Y12/Y15 grades for clearly higher strength.
Chemical composition
| Element | Content (%) |
|---|---|
| C | 0.17–0.23 |
| Si | 0.15–0.35 |
| Mn | 0.70–1.00 |
| P | ≤0.06 |
| S | 0.15–0.25 |
Weight percent, per the governing standard ranges. Actual values per heat are on the mill certificate.
Properties
| Tensile strength | 430–560 MPa (hot rolled, typ.) |
| Density | 7.85 g/cm³ |
Heat treatment
Used as-rolled or cold drawn; carbon is high enough for a modest induction-hardening response on wear surfaces.
Equivalent grades
| Standard | Designation |
|---|---|
| gb | Y20 (GB/T 8731) |
Compare side by side: Y20 vs Y15 · Y20 vs Y30
Equivalents overlap in chemistry and use but are not always identical — see our equivalents guide before substituting in certified designs.
Applications & Processing
Applications: Turned shafts, bolts, fittings and machine parts needing more strength than Y12/Y15 give.
Processing: Very good machinability; weldability still poor; the default Chinese free-cutting upgrade where Y15 parts bend or strip threads.
Need Y20 from stock?
Steel.Wiki is sponsored by Shenzhen NewAsia Special Steel (Nasteel), a special-steel stockholder in Shenzhen stocking mold, tool and alloy steels with EN 10204 3.1 certification.
Ask for a quotationVisit NasteelSource: GB/T 8731 published ranges · Last updated 2026-11-03. Data is indicative — verify critical values against the governing standard and mill certificate before use.