CuSn6 vs CuSn8: Same phosphor bronze family — CuSn8 is stronger, CuSn6 more formable
CuSn6 vs CuSn8
Side-by-side chemical composition and mechanical property comparison.
Overview
CuSn6
CW452K
Phosphor bronze with 6% tin — better cold formability than CuSn8 at slightly lower strength. Excellent spring properties and fatigue resistance. Used for electrical connectors, spring contacts, switch parts, bellows, bourdon tubes, and precision springs.
CuSn8
2.1030
Phosphor bronze with 8% tin. High mechanical strength, excellent wear resistance, good corrosion resistance (especially seawater). Self-lubricating sliding properties. Used for heavy-duty bearings, gears, worm wheels, springs, sliding elements, and connectors.
| CuSn6 | CuSn8 | |
|---|---|---|
| Material Number | CW452K | 2.1030 |
| Category | Copper & Brass | Copper & Brass |
| Standard | EN 1652 | EN 12163 |
Chemical composition (wt%)
| Element | CuSn6 | CuSn8 | Overlap |
|---|---|---|---|
| P | 0.01–0.4% | 0.01–0.4% | OK |
| Ni | 0–0.3% | 0–0.3% | OK |
| Cu | — | — | — |
| Sn | 5.5–7% | 7.5–8.5% | No overlap |
Mechanical properties
| Property | CuSn6 | CuSn8 | Unit |
|---|---|---|---|
| tensile_strength | 420–520 | 450–540 | MPa |
| yield_strength | ≥ 280 | ≥ 300 | MPa |
| elongation | ≥ 18 | ≥ 18 | % |
Compatibility Assessment
CuSn8 has ~15% higher strength due to more tin. CuSn6 has better cold formability and is more economical. Both excellent for springs and electrical contacts. Choose CuSn6 when formability matters; CuSn8 for max spring force.
Frequently Asked Questions
Is CuSn6 the same as CuSn8?
CuSn6 and CuSn8 have a 80% composition overlap. Same phosphor bronze family — CuSn8 is stronger, CuSn6 more formable
Can I replace CuSn6 with CuSn8?
In many cases, yes. The compositions overlap significantly (80%). However, always verify mechanical property requirements and heat treatment compatibility for your specific application.
What is the difference between CuSn6 and CuSn8?
The main differences are in the following elements: Sn. CuSn6 is a Copper & Brass grade, while CuSn8 is a Copper & Brass grade.
Related Comparisons
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Data provided for reference only. Always verify against the applicable specification for critical applications.
All data is for reference only. Equivalents indicate similarity, not identity. Always verify against the applicable specification for safety-critical applications. materialref.com accepts no liability for decisions based on this data.