Bleeding  Go To Index Brazing  


    Na 2 B 4 O 7 ·10H 2 O. An important mineral used in the production of boron. If copper is immersed into a borate solution before brazing of copper and then heated, it will be easier to use it in soldering. This step is called boronization. Solubility in water is 4.7 g/100 g H2O (20 ° C). At a water temperature of 60 °C , Na 2 B 4 O 7 • 5H 2 O is formed (specific gravity = 1.81). When borate is heated to 350-400 °C, it turns into anhydride. At 878 °C, it assumes a transparent, glass- like shape. Due to its ability to remove metal oxides, it is commonly used as flux in brazing.