Weldynasty Copper-Silver Brazing Flux Paste
Product Name: Weldynasty Copper-Silver Brazing Flux Paste
Type: Paste-Type Silver Brazing Flux
Standard: GB/T 15829-2021
Product Overview
Weldynasty Copper-Silver Brazing Flux Paste is a highly active paste flux designed for use with silver-based and copper-based brazing filler metals. Within the brazing temperature range of 600–860°C, it effectively removes various oxides when brazing copper, copper alloys, steel, and stainless steel, delivering strong oxide-removal capability. The product offers excellent moisture resistance, outperforming comparable products on the market.
Key Features
① Strong Oxide-Removal Capability
Within the 600–860°C brazing temperature range, it effectively removes various oxides from copper, copper alloys, steel, and stainless steel surfaces, ensuring excellent wetting of the filler metal on the base metal.
② Compatible with Multiple Filler Metals
Suitable for use with both silver-based and copper-based brazing filler metals, covering a wide range of base materials including copper and copper alloys, steel, and stainless steel.
③ Excellent Moisture Resistance
The product resists moisture absorption, remaining free from caking and sedimentation during long-term storage, with stable performance superior to comparable products.
④ Paste Form for Easy Application
The paste consistency allows for easy application and precise quantity control, suitable for flame brazing, high-frequency induction brazing, furnace brazing, and other processes.
Specifications
| Item | Specification |
|---|---|
| Form | Paste |
| Compatible Filler Metals | Silver-based, Copper-based |
| Brazing Temperature Range | 600–860°C |
| Applicable Base Metals | Copper & copper alloys, steel, stainless steel |
| Standard | GB/T 15829-2021 |
Reference Composition (Typical Formulation)
Note: The specific formulation of this product is proprietary technical information. The following is a typical reference composition for silver brazing fluxes of the same type (QJ102 system), provided for technical selection reference. Actual composition is subject to the product's factory inspection report.
| Component | Mass Fraction (%) | Function |
|---|---|---|
| Potassium Fluoride (KF) | 40–44 | Primary activator; lowers melting point and enhances oxide removal |
| Potassium Fluoroborate (KBF₄) | 21–25 | Activator; decomposes at high temperature to release BF₃ for enhanced oxide removal |
| Boric Anhydride (B₂O₃) | 33–37 | Slag-forming agent; reacts with metal oxides to form soluble borates |
Composition System Description:
This flux system uses potassium fluoride (KF) as the core active component, which dissolves and breaks down the oxide films on base metal and filler metal surfaces during brazing, reducing surface tension between the liquid filler metal and base metal to promote wetting. Potassium fluoroborate (KBF₄) melts at approximately 540°C and decomposes into KF and BF₃. The released BF₃ possesses extremely strong oxide-removal capability, reacting with refractory oxides such as Cr₂O₃ to form volatile fluorides. Boric anhydride (B₂O₃) reacts with metal oxides to form soluble borates, further lowering the active temperature.
Tip: The composition above represents typical industry reference data for silver brazing fluxes of the same type. Weldynasty's actual formulation may be adjusted based on specific performance requirements. Please contact our sales team for the factory inspection report to obtain precise composition data.
Applications
Air-conditioning and refrigeration piping brazing (copper tubes, copper alloy fittings)
Stainless steel vacuum cups, kettles, and household products
Carbide cutting tools and diamond polycrystalline compact brazing
Eyeglass frames, jewelry, and hardware tools
Motors, compressors, valves, and other component brazing
Usage Recommendations
Stir thoroughly before use and apply evenly to the welding area.
For best results, use with silver-based or copper-based brazing filler metals.
Remove residual flux after brazing (depending on flux corrosiveness).
Quality Assurance
Weldynasty Copper-Silver Brazing Flux Paste is manufactured strictly in accordance with GB/T 15829-2021. Each production batch is performance-tested to ensure activity, stability, and moisture resistance meet requirements.