Boron compounds are used as protective slag formers and melt accelerators in the non-ferrous metal industry due to their ability to form smooth, adhesive, protective and burr-free liquids at high temperatures.
In flux application, boron is used for melting copper alloys, for gold analysis and refining, during solder welding of steel and for gas soldering.
The addition of boron increases the hardness and strength of the steel. Steels can contain up to 50 ppm boron. Boron steels have higher hardenability. Boron is also added to stainless steels.
Ferroboron is used in production of steel, cast iron, permanent magnets and amorphous metals. More than 50% of the world ferroborne production is used in the steel industry. 10% of the production is used in the production of Nd-Fe-B permanent magnets.
Another application using boron compounds is boronizing. Hardening of steel surfaces is increased by boronizing. Boronized steels have a high degree of corrosion and abrasion resistance and are especially used in applications such as polishing surfaces of hydraulic tools and some oil-well drilling drills. In addition, boronized materials are used in the automotive industry to reduce the coefficient of friction and to protect moving parts.
Boron nitride is widely used in surface coating due to its effect on reducing the coefficient of friction. The coating process is carried out by evaporating the h-BN under high vacuum and suitable temperature to obtain a c-BN film.
Boron chemicals are also used as cleaners and buffers in electroplating applications. Boric acid and flouroborates are used in very small amounts to reduce the pore and pit of the deposits, while flouroboric acid is used at a level of 10% for pickling of tin-plated wires.
Boron fibers are used in many fields, from sports equipment (fishing, golf, skiing, cycling) to space and aircraft. Boron fiber composites consist of polymer resins reinforced with boron fibers. Boron fiber composites are the first advanced composite materials used in the production of air and space vehicles. The high costs of boron fibers limit their use.
Space and Aviation
The use of boron in the aircraft and aviation industry has been increasing. Developments in aerodynamics, high-speed wing applications, high temperature resistant body, low weight, high capacity and similar applications on design and development studies have made widespread use of composite materials in space and aviation industry.
Boron is considered as an advantage in transportation vehicles because it is flammable but has a high ignition temperature, gives solid products, which can easily be transferred as a result of combustion and does not emit pollutant emissions.
Boron chemicals can be used as missile fuel and there are studies on the use of borohydrides as high performance potential fuels in aircraft such as hydrogen diborane (B2H6) and hydrogen pentaborane (B5H9).