Welcome to the aluminium brazing blog site. We will regularly be publishing articles about aluminium brazing in this blog and we look forward to your comments, remarks and questions. Behind the scenes in this blog are the specialists for aluminium brazing from Solvay Fluor. This blog is a corporate blog and offers you new, additional ways to communicate with us.
Case Study A radiator core retrieved from service was examined for a suspected premature corrosion related failure. Upon closer metallographic examination, no evidence of corrosion was found at the failed area. Header: AA4343/ AA3005 Tube: AA4343/ AA3003 It was concluded that the cause of the failure was […]
Experimental The effect of temperature on filler metal erosion was studied using an automotive radiator core. In this case, joining progresses initially as expected. The cladding layer on the tube melts and flows by capillary action to the fin to tube joint and a normal fillet forms. However, as the peak brazing temperature is allowed […]
The European Association for Brazing and soldering — EABS for short — together with experts from Solvay Fluor, holds technical training seminars in which the theory and practice of flame and furnace aluminium brazing are communicated in detail. 40 interested participants from all over the world gather for the two day seminar in Hannover, Germany: […]
HF can potentially be formed during the flux brazing process. HF is very toxic, irritating to the eyes, skin and respiratory tract and cause severe burns of the skin and eyes. The threshold limit value (TLV) for HF is a ceiling concentration of 3 ppm (2.3 mg/m3), a concentration that should not be exceeded during […]
How to obtain? A lot of information can be gained from heat exchanger brazing cycle temperature profile. It is probably one of the most important pieces of information that the brazing engineer can use to fully understand his process. A temperature profile will provide information such as heating rate, maximum peak brazing temperature, time at […]
Furnace atmosphere The recommended furnace atmosphere conditions necessary for good brazing are as follows: Dew point: ≤ -40°C Oxygen: < 100 ppm Inert gas: nitrogen The most common source of nitrogen is that generated from liquid nitrogen storage tanks. A typical nitrogen gas specification from a liquid source indicates that the moisture content is <1.5 […]
As manufactured, a non-corrosvie K-Al-F-type flux typically is a mixture of potassium tetra-fluoroaluminate (KAlF4), and also contains potassium penta-fluoroaluminate (K2AlF5). K2AlF5 exists in different modifications: potassium penta-fluoroaluminate hydrate (K2AlF5 · H2O), and hydrate-free (K2AlF5). During the brazing process, the material undergoes essential physico-chemical alterations. While the chief component, KAlF4, is simply heated up, the compound […]
Process related causes The service life of a heat exchanger may be shortened due to corrosion caused by process related events. Some examples are listed below: Excessively high brazing temperature or too long time at temperature will lead to excessive Si diffusion in the core. Si diffuses along grain boundaries and this can increase the […]