Phosphor Bronze Washers | Phosphor Bronze Spring Washers | PB Flat Washers | Bronze Lock Washers
Manufacturer–Exporter from India of Bronze washers
Overview
We are a specialist manufacturer and exporter of Phosphor Bronze Washers, Phosphor Bronze Spring Washers, Phosphor Bronze Flat Washers, Phosphor Bronze Lock Washers, and Phosphor Bronze Shim Washers from India. Produced from high-tin phosphor bronze alloy strip (C51000, C52100, C54400), our phosphor bronze washers offer an exceptional combination of spring elasticity, wear resistance, low coefficient of friction, electrical conductivity, and outstanding corrosion resistance in marine, chemical, and humid environments. We export phosphor bronze washers to manufacturers of electrical connectors, instrumentation, marine hardware, springs, and precision mechanical assemblies across the USA, UK, Germany, Japan, Australia, and the Middle East.
What Are Phosphor Bronze Washers?
Phosphor bronze is a copper-tin-phosphorus alloy renowned for its excellent spring properties, high fatigue strength, low magnetic permeability, and natural corrosion resistance. Phosphor bronze washers are used wherever steel washers would corrode, brass washers lack sufficient spring resilience, or non-magnetic material is required. Related terms include: PB washers, tin-bronze washers, CuSn6 washers, CuSn8 spring washers, C51000 washers, bronze spring lock washers, phosphor bronze disc springs, phosphor bronze shim rings, copper-tin alloy washers, and anti-corrosion spring washers.
Material Grades & International Equivalents
| Grade | CDA (USA) | EN / CW | DIN | Sn% | Key Property |
|---|---|---|---|---|---|
| PB1 | C51000 | CW451K | CuSn6 | 5.0–7.0 | Balanced spring + conductivity |
| PB2 | C52100 | CW453K | CuSn8 | 7.5–8.5 | Higher strength and wear resistance |
| Bearing Bronze | C54400 | CW455K | CuSn4Pb4Zn3 | 3.5–4.5 | Free-machining, bearing quality |
| High Fatigue | C51900 | CW452K | CuSn6P | 5.5–7.0 | Max phosphorus, highest fatigue life |
BS (UK): PB1 and PB2 per BS 2870 | IS (India): IS 7811 Grade 1 and Grade 2 | JIS (Japan): C5191, C5210 | MIL-SPEC: MIL-C-21768, MIL-B-13501
Types of Phosphor Bronze Washers We Manufacture
Our range includes: Phosphor Bronze Flat Washers (DIN 125, ISO 7089 equivalent), Phosphor Bronze Spring Lock Washers (DIN 127B, DIN 128), Phosphor Bronze Wave Washers (single and multi-wave), Phosphor Bronze Belleville / Disc Springs, Phosphor Bronze Shim Washers (precision ground, ±0.01 mm), Phosphor Bronze Tab / Locking Washers, Phosphor Bronze Thrust Washers (bearing-grade C54400), and Phosphor Bronze Repair / Oversize Washers.
Design & Manufacturing Capabilities
Thickness range: 0.1 mm to 8 mm. OD range: 5 mm to 200 mm. ID range: 2 mm to 150 mm. Hardness (spring temper): HV 180–230 (1/4 Hard to Full Hard). Tolerances: OD ±0.05 mm, ID ±0.03 mm, thickness ±0.01 mm. Surface finishes: natural, polished bright, electrolytic tin-plated, silver-plated, hot-dip tinned. Die types: progressive, compound, fine blank. Secondary operations include annealing, coining, deburring, plating, and assembly.
Technical Specifications
| Property | C51000 (CuSn6) | C52100 (CuSn8) |
|---|---|---|
| Tensile Strength (Spring Temper) | 500–700 MPa | 600–800 MPa |
| Yield Strength (0.2%) | 350–550 MPa | 450–650 MPa |
| Elongation | 8–15% | 5–10% |
| Hardness (Spring Temper) | HV 180–210 | HV 210–240 |
| Elastic Modulus | 110 GPa | 112 GPa |
| Electrical Conductivity | ~15% IACS | ~13% IACS |
| Max Operating Temp | 150°C | 150°C |
| Corrosion Resistance | Excellent | Excellent |
Applications & Industries
Electrical & Electronics (connector spring contacts, relay parts, PCB hardware), Marine Hardware (non-magnetic, corrosion-resistant fastener washers for shipboard use), Instrumentation (precision shim washers for gauge and sensor assembly), Bearings & Bushings (thrust washers and plain bearing shims in C54400), Spring Assemblies (multi-wave washers for preload in motors and actuators), Oil & Gas (non-sparking washers in hazardous areas), Watches & Clocks (ultra-thin precision washers), and Defence / Ordnance (non-magnetic components for mine-safe assemblies).
ISO Certification & Quality Assurance
We hold ISO 9001:2015 certification. Phosphor bronze washer quality controls include: incoming strip chemical analysis, hardness, and tensile verification per EN 13599 / ASTM B139; in-process dimensional AQL sampling every production run; final spring load testing (wave and disc washers), conductivity testing, and plating adhesion checks. Certificates provided: EN 10204 3.1 MTC, RoHS, REACH SVHC Declaration, Certificate of Conformity.
Frequently Asked Questions
Q1. What is the advantage of phosphor bronze washers over stainless steel spring washers?
Phosphor bronze offers superior spring fatigue life in electrical and electronic environments, is non-magnetic (important in MRI and compass applications), has better conductivity (15% IACS vs <1% for SS), and resists seawater and atmospheric corrosion better than standard 304 stainless steel.
Q2. Can phosphor bronze washers be used in marine applications?
Absolutely. Phosphor bronze (particularly C51000 and C52100) has excellent saltwater corrosion resistance and is widely specified for marine deck hardware, shipboard instrumentation, and offshore electrical connectors.
Q3. What is the difference between C51000 and C52100 phosphor bronze?
C51000 (CuSn6) offers a balance of spring properties and electrical conductivity. C52100 (CuSn8) has higher tin content, giving greater strength, hardness, and wear resistance at the cost of slightly lower conductivity — ideal for demanding spring and bearing applications.
Q4. Do you supply phosphor bronze washers in spring temper?
Yes. We supply in annealed (M), quarter-hard (H01), half-hard (H02), three-quarter-hard (H03), and full-hard (H04) tempers per ASTM B139. Spring / extra-hard temper is standard for lock and spring washer applications.
Q5. Can phosphor bronze washers be tin-plated for solderability?
Yes. Electrolytic tin plating (5–10 µm) improves solderability, prevents tarnishing, and improves contact reliability for electrical connectors. Hot-dip tinning is also available for high-volume electronic assembly applications.
Q6. What is the MOQ for phosphor bronze washers?
For standard sizes, MOQ is 500 pcs. For custom sizes requiring tooling, MOQ is 5,000 pcs. We welcome sample and trial orders. Competitive pricing starts from USD 12–20/kg CIF depending on grade and quantity.
Why Choose us for Phosphor Bronze Washers?
30+ years of phosphor bronze press-part expertise | Non-magnetic, RoHS-compliant materials | Export to 40+ countries in marine, defence, electronics, and instrumentation sectors | Standard items ex-stock; custom tooling in 4–6 weeks | Full certification: EN 10204 3.1 MTC, CoC, RoHS, REACH | Flexible order sizes from trial to bulk production.
Request a Quote – Phosphor Bronze Washers and Spring Washers
Tell us your OD, ID, thickness, required temper/hardness, plating requirement, quantity, and application — we will respond within 24 hours with pricing and a material data sheet. Email: sales@cableglandsindia.com | Phone: +91 22 4344 9300. Download our catalogue or request a sample today.