Fluoboric Acid 48% is used in aluminum etching and acid pickling. If the aluminum alloy contains silicon (as in cast aluminum) fluoboric acid is necessary for effective de-smutting and de-oxidizing. It is employed for grain structure analysis for certain alloys. It also plays a role in flame-retardant materials and glazing frits, as well as in the electrolytic generation of boron.
In the electroplating field it is used in high-speed plating of copper in fluoroborate baths. At one time it was also commonly used in plating of tin and tin alloys, however in this application methane sulfonic acid has displaced the usage.