Active surface finishing with a brazing agent
NOCOLOK® Flux is the world’s most widely used flux for aluminium brazing in a controlled atmosphere. Well-proven in the automotive industry, NOCOLOK® Flux is also increasingly used for brazing aluminium coolers for air conditioning and refrigeration systems. In the well-known standard applications NOCOLOK®Flux is not corrosive. To improve the positive properties under extreme conditions even further, Solvay Fluor, has developed a new brazing agent for the markets: NOCOLOK® Li Flux.
This new flux builds a very smooth surface residue. The new physical-chemical properties present an optimization of the compatibility in hydrous environments. NOCOLOK® Li Flux has passed several test series with good results and is meanwhile in the testing phase in many companies.
Is there any big difference between cost of Conventional Fl-7 flux and that of Li flux. What are the significant benefits of using Li flux
Controlled Atmosphere Brazing (CAB) with potassium fluoroaluminate fluxes continues to be a worldwide standard technology used for the production of all-aluminium heat exchangers. It has been demonstrated, by means of corrosion testing methods (e.g., SWAAT; CASS, NSS ), that a residual flux layer improves the corrosion resistance when compared with bare parts*.
It has been found that under the right conditions the exposure of brazed aluminium substrates to low flow rate (stationary) aqueous media over an extended period of time can potentially lead to specific surface reactions**. The main factors involved in such interactions are flux residue solubility and dissolution.
To address this issue, Solvay Fluor has developed a new NOCOLOK® composition with improved flux residue performance. When using the new flux, potential surface reactions of brazed aluminium surfaces with water are significantly reduced.
The new NOCOLOK® Li Flux shows the same outstanding properties and brazing performance of standard potassium fluoroaluminate flux – with further enhancement of the post braze flux residue characteristics.
For more information please refer to the attached technical brochure.
* “Influence of Residual Flux Level on the Corrosion behavior of CAB Alloys.” A. Gray et. al. International Aluminium Brazing Congress, Dusseldorf; 2002.
**”Study on the Hydrolysis of Post-Braze Flux Residues” P.García and H. Swidersky. 13th Invitational International Aluminum Brazing Seminar, Novi; 2008.
For more information about NOCOLOK® Li Flux, please refer to our website: http://www.solvay-fluor.com/product/lib/0,0,-_EN-1000837,00.html
On your commercial question, please contact Werner Schmitt: werner.schmitt(at)solvay.com.
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