Höganäs’ newly developed BrazeLet 9007/9017 water-based pastes for dispensing are flux free, contain low polymer content and prevent oxidation of the filler metal. They enable brazing with lower emissions and provide a healthier workplace.

“Our customers struggled with some big issues which is why we started this new development,” explains Lisa Kjellén, manager for brazing development. “Firstly, the decomposition of organics in brazing pastes leads to the formation of residues which accumulate in the furnace and pumps. This results in higher costs for maintenance and could even cause production stops. Also, the oxide formation in the brazed joint is a common issue with certain filler metals. The visual appearance of the brazed joint is then impacted, and more paste may need to be applied to properly fill the gaps.”

Current industry practices are problematic due to major drawbacks regarding health hazards. The addition of flux to the binder might help avoid the formation of oxides in the joint, however, flux compounds are also on restriction lists due to health risks. Moreover, flux does not prevent the formation of organic residues.

Höganäs’ newly developed brazing pastes BrazeLet DW-9007/9017 solve these challenges. The paste is characterized by its high metal content and a very low polymer. Furthermore, it does not contain any flux additives.

“The binder burns off cleaner, generating lower amounts of volatile organic compounds and therefore less residue accumulation in the furnaces. All of this while preventing the oxidation of the brazed joint. Additionally, all the ingredients used in the binder come from renewable sources, which is in line with Höganäs’ sustainability approach,” explains Kjellén.

Typical applications can be found in the automotive as well as heating, ventilation, air condition (HVAC) industries for components such as brazed plate heat exchangers, exhaust gas recirculation (EGR) coolers or oil coolers. BrazeLet DW-9007/9017 are part of Höganäs’ extensive portfolio of nickel and iron-based filler metals for high temperature brazing.

“As a global leader in metal powders, Höganäs has in-depth knowledge about metal alloys and the capabilities to tailor our materials according to the specific requirements of our customers,” explains Hans Söderhjelm, SVP research and development. “Our tech center, which is equipped with state-of-the art brazing equipment, enables us to assist our customers throughout their complete brazing value chain. Höganäs offers support from the selection of the right filler metal to consultancy with regards to paste application method and brazing process.”