Luoyang Hongsheng Trading Co., Ltd. (HSMetal) has completed another export shipment of Custom C51900 Phosphor Bronze Strip to an industrial component manufacturer in Turkey. The material is being used for high-reliability relay spring contacts in household electrical control devices.
As a premium lead-free spring phosphor bronze alloy, C51900 Phosphor Bronze (CuSn6 / CW452K) fills the performance gap between general-formability C51000 and ultra-high-strength C52100. It integrates excellent elasticity, long-term fatigue resistance and stable corrosion resistance, making it the ideal material for electrical connectors, instrument springs, switch elements and 5G RF components that require stable performance under millions of repeated flexing cycles. To learn more about performance differences and application scenarios between mainstream phosphor bronze grades, you can browse our professional phosphor bronze material selection guide for detailed industry knowledge.
Project Background & Strict Customer Technical Requirements
The Turkey customer is a local mainstream manufacturer of household electrical control components, with extremely strict standards for raw material stability and batch consistency. This cooperation is aimed at core relay spring contact parts, which serve high-frequency switching electrical equipment and have ultra-high requirements for material comprehensive performance.
The core technical and quality requirements of the project are as follows:
- Customized specifications: 0.65mm thickness, 1/2H temper C51900 phosphor bronze strip
- High-cycle fatigue performance: Maintain stable spring force without attenuation after more than 500,000 flexing cycles
- Compliance standard: Fully meet RoHS lead-free environmental protection requirements
- Precision tolerance requirement: Ultra-tight flatness standard, adapting to the customer's high-speed progressive stamping mass production line
Such strict multi-dimensional indicators are far beyond the production capacity of ordinary bronze suppliers, bringing great challenges to our production and technical team.
Targeted Technical Research & Production Breakthroughs
Facing the stringent technical thresholds, our technical team did not adopt conventional production processes. Instead, we launched special project research, targeted at the two core pain points of uniform hardness stability and thin-strip flatness control for 0.65mm ultra-thin phosphor bronze strip, and completed full-process process optimization and technical upgrading.
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Optimized Precision Rolling Process
Aiming at the problem of easy thickness deviation and uneven stress of thin strips, we adjusted the rolling speed, pressure and temperature parameters in real time, realizing uniform thickness tolerance of the whole strip and avoiding local hardness difference, which ensures consistent spring performance of each stamped part.
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Professional Stress-Relief Annealing Treatment
For the hidden risk of spring force attenuation after long-term cyclic use caused by internal residual stress, we formulated a personalized low-temperature stress-relief annealing scheme. This process completely eliminates internal processing stress, effectively guarantees the material's high-cycle fatigue resistance, and ensures stable elasticity after 500,000+ flexing tests.
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Strict Batch Quality Inspection System
We implemented full-process tracking inspection from raw material feeding to finished product delivery. Each batch of products undergoes repeated testing on hardness, flatness, dimensional tolerance and fatigue performance, and finally provides complete Mill Test Certificate and mechanical performance test reports to support customer incoming inspection.
Customer-Centric Full-Link Service Solution
Throughout the project, we always stood in the customer's production perspective, focusing on solving the customer's actual production difficulties and potential risks, rather than simply delivering qualified products.
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Customized Processing Matching Customer Production Line
According to the customer's local high-speed progressive stamping equipment parameters, we completed accurate custom slitting and fixed-size cutting, optimized the strip flatness and edge smoothness, effectively avoiding stamping jamming, deformation and defective rate increase during the customer's mass production.
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Advance Risk Prevention & Technical Communication
In the early stage of cooperation, our engineers actively communicated with the customer's production team, sorted out key production risk points in advance, and provided targeted material use and stamping process suggestions, helping customers shorten the trial production cycle and improve production efficiency.
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Efficient After-Sales & Quality Assurance
During the production and delivery cycle, we provided real-time production progress feedback. After the goods arrived in Turkey, we followed up the customer's laboratory testing and production trial operation throughout the whole process, ensuring zero obstacles for customer mass production.
Project Operation Results & Customer Feedback
After strict laboratory testing and on-site production verification by the Turkey customer, this batch of customized C51900 phosphor bronze strip fully meets all technical indicators and environmental compliance requirements. At present, the materials have been running stably on the customer's automated stamping production line for a long time, with no quality problems such as unstable spring force, poor flatness and fatigue failure. The customer highly recognized our precise customization capability, stable product quality and professional technical service.
What This Case Proves About Our Capability
This project demonstrates what we bring to high-cycle spring contact applications:
| Our Capability | How It Helped This Customer |
|---|---|
| In-house melting to finished strip | Full control over composition, temper, and flatness |
| Precision rolling & annealing | Consistent hardness and flatness for progressive stamping |
| Custom slitting | Ready-to-stamp blanks, less waste, faster production |
| Full MTC & batch records | Fast, predictable incoming QC |
| Turkey export experience | Smooth customs, CE packaging, local language support |
| Engineering support | Right grade and temper recommendation, not just material supply |
For Buyers with Similar Projects
If you are sourcing phosphor bronze strip for relay springs, connector contacts, or other high-cycle flexing applications, share your:
Temper requirement (1/2H, H, EH, SH)
- Dimensions (thickness, width, coil weight)
- Cycle-life target (e.g., 500,000+ flexing cycles)
- Compliance needs (RoHS, ASTM B103, EN 1652)
Our engineering team will recommend the right grade, temper, and slit width - and provide a sample for your evaluation before you commit to production volume.
→ [Request a Quote] | [Grade Selection Guide] | [Contact Turkey Sales Team]
Future Service Outlook
We will continue to adhere to the customer-centric concept, focusing on independent R&D and precision production of high-performance phosphor bronze alloys. As demonstrated in this Turkey high-cycle spring project, our C51900 Phosphor Bronze Strip delivers balanced elasticity and fatigue resistance for precision electronic and electrical applications. For engineers looking for accurate grade matching and technical parameters, our comprehensive phosphor bronze material selection knowledge base systematically sorts out the applicable scenarios, mechanical properties and processing differences of C51000, C51900, C52100 and C54400. We continuously provide global manufacturers with one-stop customized material solutions covering grade selection, temper customization, precision cutting, full inspection reports and professional technical support, helping overseas clients avoid material selection errors and achieve stable, high-quality mass production.
FAQ
Q1: What is C51900 phosphor bronze used for?
A:C51900 (CuSn6) is primarily used for spring contacts, connectors, relay parts, and electrical terminals. Its 6% tin content delivers the elasticity and fatigue resistance needed for components that flex repeatedly in service. Common end products include relay springs, connector contacts, switch elements, and precision stamped parts.
Q2: What temper should I choose for spring contact applications?
A:For high-cycle spring contacts (500,000+ flexing cycles), we recommend 1/2H or H temper. This balances the spring force you need with enough formability for progressive stamping. For less demanding forming, soft or quarter-hard tempers offer better bendability at lower strength.
Q3: What is the difference between C51900 and C51000?
A:C51900 contains 6% tin vs 5% tin in C51000. The higher tin gives C51900 greater strength and fatigue resistance (tensile strength up to 620 MPa vs 480 MPa for C51000). C51000 is easier to form and slightly cheaper, making it suitable for less demanding spring applications.
Q4: Is C51900 RoHS compliant?
A:Yes. C51900 is a lead-free phosphor bronze with lead content typically ≤0.02%. It meets RoHS requirements and is suitable for electrical and electronic applications in regulated markets.
Q5: What thickness and width can you supply?
A:Standard C51900 strip: thickness 0.05–2.0mm, width 10–600mm. Custom slit widths are available to match your stamping line specifications, reducing in-house slitting and material waste.
Q6: What makes C51900 phosphor bronze suitable for high-cycle relay spring components?
A: C51900 Phosphor Bronze features a balanced ratio of tin and phosphorus composition, delivering excellent fatigue resistance and stable elastic recovery. It can maintain consistent spring force without attenuation after 500,000+ repeated flexing cycles, perfectly meeting the long-term stable operation requirements of relay contacts and electrical switch components, which is verified by our successful Turkey customer project.
Q7: Can you provide customized temper and precision size processing?
A: Yes. We support full customization of thickness, width, temper and flatness tolerance. For high-speed progressive stamping production scenarios like the Turkey client's factory, we provide professional custom slitting, fixed-size cutting and stress relief treatment to ensure zero jamming and low defective rate during mass production. Multiple tempers including 1/2H, H, EH and SH are available for different spring application demands.
Q8: Do you provide official quality certification documents for every shipment?
A: Absolutely. Each batch of our phosphor bronze products is accompanied by complete Mill Test Certificate (MTC), covering chemical composition, mechanical properties, hardness and flatness test data. We can also support third-party inspection as required by buyers to meet factory incoming inspection and project compliance standards.
Q9: Is C51900 phosphor bronze RoHS compliant?
A: Yes. C51900 CuSn6 phosphor bronze is a lead-free environmentally friendly alloy, fully compliant with RoHS environmental protection standards. It is widely applicable for civilian electrical equipment, electronic components and 5G communication parts, solving the compliance risks faced by overseas electronic manufacturing enterprises.
Q10: How to choose the right phosphor bronze grade for my production project?
A: Different phosphor bronze grades have distinct performance positioning: C51000 for high-formability general stamping parts, C51900 for high-cycle fatigue spring components, C52100 for higher wear and corrosion resistance, and C54400 for high-volume CNC machining parts. You can refer to our phosphor bronze material selection knowledge base for professional grade selection guidance, or consult our engineering team for one-to-one tailored material solutions.
Q11: What is your delivery and after-sales service guarantee for export orders?
A: We provide standardized export packaging suitable for long-distance sea transportation to avoid deformation and oxidation. We offer real-time order progress tracking throughout production and shipment. For overseas customers, we provide long-term technical after-sales support, including material usage guidance, stamping process suggestions and problem troubleshooting, ensuring stable and continuous mass production for buyers.
Q12: What certifications come with the material?
A:Every shipment includes Mill Test Certificate (MTC) with chemical composition, mechanical properties, and heat number traceability. We also provide batch mechanical test records (hardness, tensile strength) and RoHS compliance declarations.
Q13: Can you supply to Turkey?
A:Yes. We have established export logistics to Turkey with pre-cleared HS code documentation (7409.90) and CE-compliant packaging. Typical delivery to Istanbul is 20–30 days including customs clearance. Turkish-language QC reports available on request.
Q14: What is your MOQ and lead time?
A:MOQ: 100kg per size for standard strip. Lead time: 15–25 days after deposit for standard sizes. Custom slit widths or special tempers: 20–30 days.
