Boriding of Steel – All You need to know

oriding steel is a procedure for the treatment of Fe-based metals that provides a wide range of benefits. This includes improved mechanical properties such as higher surface hardness, corrosion resistance, resistance to temperature and acids and reduced tendency to cold weld. Steel is one of the most widely used materials in construction and engineering of our time, worldwide. It is for example used for the construction of buildings, bridges, power poles and oil drilling platforms as well as the manufacturing of cars, planes, ships and machine components of various shapes and sizes. Some of those need special treatments such as boriding steel to obtain maximum functionality and meet the highest demands for quality.

Boriding of steel provides several desirable properties

Surface treatments confer several properties on the processed material. It is thus possible to achieve a hardness of up to 1900 HV in ferrous materials, reduce the coefficient of friction and increase the resistance to hydrochloric acids and high temperatures. Depending on the base material, the thickness of the boride layer varies between 10 and 200 µm. Boriding steel generally results in a thicker layer due to the higher content of higher amount of ferrous elements. Ni, Ti or Co alloys on the other hand are able to develop a micro-hardness even higher than FeB2 or FeB.

Typical applications for the boriding process

Besides the above-mentioned properties, the boride layer also provides a reduced tendency to cold weld and higher wear resistance and is therefore applicable to a wide range of tooling applications. The Oil & Gas Industry for example relies on boriding steel to harden the surface of metal seals, valve components, fittings and burner nozzles. Further applications are turbine components, ball valves, dies, pump impellers, plungers, gears and shafts. The treatment is selectively applicable to irregular sizes and shapes, the materials can be hardened to an even higher extent with other heat treatments afterwards. Common materials for boriding steel are for example plain carbon steels, stainless steel, tool steels, low alloy steels and cast iron. Furthermore, non-ferrous metals such as Tantalum, Molybdenum, Niobium, Titanium and several alloys based on Ti and Ni.

How can you protect steel with boriding?

Our BORINOX® process allows you to harden stainless steel without deteriorating the corrosion properties, protects against abrasion, cold welding, cavitation, increases fatigue strength, improves the coefficient of friction, is corrosion resistant and dimensionally stable.