30
Data verified30 is the GB/T 699 grade matching AISI 1030 / JIS S30C — the first GB carbon grade with useful quench-and-temper response in small sections.
Chemical composition
| Element | Content (%) |
|---|---|
| C | 0.27–0.34 |
| Si | 0.17–0.37 |
| Mn | 0.50–0.80 |
| P | ≤0.035 |
| S | ≤0.035 |
| Cr | ≤0.25 |
Weight percent, per the governing standard ranges. Actual values per heat are on the mill certificate.
Properties
| Tensile strength | ≥500 MPa (GB/T 699 reference, normalized blank) |
| Yield strength | ≥295 MPa (reference) |
| Density | 7.85 g/cm³ |
Heat treatment
Normalize; quench and temper small sections; flame hardening possible for wear surfaces.
Equivalent grades
| Standard | Designation |
|---|---|
| din | 1.0528 (C30) |
| aisi | 1030 |
| jis | S30C |
| gb | 30 (GB/T 699) |
Compare side by side: 30 vs 1030
Equivalents overlap in chemistry and use but are not always identical — see our equivalents guide before substituting in certified designs.
Applications & Processing
Applications: Shafts, levers, bolts, coupling parts, fan and pump components.
Processing: Weldable with care as carbon rises; machines well normalized.
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Ask for a quotationVisit NasteelSource: GB/T 699-2015 published ranges · Last updated 2026-11-03. Data is indicative — verify critical values against the governing standard and mill certificate before use.