Potassium Pentaborate

Metal refining and metallurgy

Borates are used as cover fluxes in metal refining. Potassium pentaborate is an excellent choice for copper refining, copper alloys, and precious metals. As an alternative to typical fluorine-containing flux compounds, potassium pentaborate can help reduce fluorine emissions.

When using silver soldering, brazing, or welding to join metals, use potassium pentaborate by itself or mixed with other materials to create a borate-containing flux. This flux melts and dissolves oxide impurities on the metal surfaces that are being joined and provides a protective barrier film that prevents further oxidation. Use potassium pentaborate in fluxes for stainless steel or various non-ferrous metals to avoid the glare that is associated with sodium borate.

Gear lubrication

When dispersed in a very finely divided state, potassium borates improve the load-carrying, anti-corrosion, and anti-wear properties of industrial and automotive gear lubricants. Under extreme conditions, potassium pentaborate interacts with metal load-bearing surfaces to form a film of extraordinary resilience. This tenacious film provides outstanding load-carrying capacity and wear protection, making the product an ideal fit in automotive lubricants.

Oil well drilling

Slow-setting cements can be pumped to great depths before hardening during oil well drilling. The addition of soluble borates such as potassium pentaborate delays the set of the cement.

And, more

Other uses include in photographic development, where potassium pentaborate can be used as the source of borate anion. In a complex with cationic dye, the product can then be combined with a nonionic aromatic diazo compound to create a light-sensitive composition for use as a diazotype developer.

Potassium pentaborate solutions are also used to treat wooden and paper matches to control the burn rate of the match and to stop afterglow.