Phosphor-Bronze Compression Spring

描述

1. Performance
   • Excellent Electrical Conductivity – Rolled-and-drawn C51000 phosphor-bronze wire (97 % Cu, 2.1 % Sn, 0.2 % P) offers bulk resistivity ≈ 1.6 µΩ cm, enabling simultaneous mechanical force and stable signal or grounding paths.
   • High Fatigue Strength – Cold-worked wire is oil-tempered and double stress-relieved at 260 °C, reaching 1 200 – 1 500 MPa tensile strength with <2 % permanent set after 500 000 full-stroke cycles.
   • Corrosion Resistance – Tin-rich alloy forms a self-healing oxide that resists sulphur, mild acids, and seawater vapour; optional gold or silver flash (<2 µm) further improves contact reliability in low-voltage circuits.
   • Dimensional Versatility – Wire Ø0.3 – 1.5 mm, outer Ø1.9 – 14 mm, and free lengths up to 150 mm cover micro-switch contacts through to medium load supports; conical or barrel profiles can shorten solid height or deliver progressive force curves.
2. Application Scenarios & Assembly Requirements
   • Signal & Ground Contacts – Relay plungers, battery holders, slip-ring brushes, and PCB test probes where low contact resistance and moderate spring force are critical.
   • EMI Shielding Fingers – Provide continuous pressure along chassis seams in telecommunication racks and aerospace housings, maintaining <20 mΩ joint resistance after vibration testing.
   • Precision Valves & Meters – Non-sparking, non-magnetic alloy suits oxygen service, gas flow regulators, and measuring instruments exposed to moisture or chemicals.
   • Assembly Guidelines
   – Seating Surfaces: use electroless-nickel or noble-metal pads to minimise galvanic mismatch and fretting.
   – Guide Clearance: bore ID = spring OD + 0.10 × wire Ø to avoid side-load buckling.
   – Compression Limit: cap stroke at 80 % of solid height to retain ≥ 95 % initial load over one million cycles.
   – End Style: squared-and-ground ends ensure concentric force in conductive paths; closed-unground ends acceptable for plastic seats.
3. User-Friendly Operation
   • Pre-Scragged & Calibrated – Springs are compressed to solid twice during production; published force values are valid right out of the box with no break-in period.
   • Clean Handling – Supplied ultrasonically cleaned and vacuum-bagged to prevent surface oils that raise contact resistance; compatible with IPA or mild alkaline washes before assembly.
   • Quick Identification – Laser-etched alphanumeric code on the last coil encodes wire size, free length, and plating type for rapid line-side sorting.
   • Tool-Free Installation – Small sizes seat with fingertip pressure; longer coils slide over standard guide pins—no special compressors or lubricants required.
4. Quality & Longevity
   • Certified Production – ISO 9001 / IATF 16949 processes with in-line laser gauging keep force tolerance within ±6 % and free-length tolerance within ±0.5 mm.
   • Fatigue & Contact Life – Laboratory tests show <3 % load loss after 1 000 000 cycles at 60 % solid height; contact resistance remains under 25 mΩ after 10 000 mating cycles and 48 h mixed-flowing-gas exposure.
   • Surface Finish Options – Chemical tin, bright nickel, silver, or 24 ct gold (all ≤ 5 µm) available to match application voltage and corrosion demands without altering spring rate.
   • Full Traceability – Each batch is linked to 3.1 material certificates, furnace charts, and individual load/deflection curves, ensuring predictable, auditable performance for medical, aerospace, and telecom applications.