Types of Hard Facing

Hardfacing with precious alloys makes it possible to ennoble, at a contained cost, base materials of a low cost. Current knowledge puts this technology among those able to provide an increased benefit in terms of increasing production, due to fewer machine stops resulting in higher efficiency of the hardfaced pieces.

It is normally carried out on shafts, bushings, and guides in carbon steel or cast iron, to give the surfaces in contact with other metal (carbon steel, tempered, stainless, etc.) characteristics similar to that obtained with bearings. The costs are much more contained as the dimensions of the pieces to refill increase. The Hardfacing can be done on one side or the other of the coupling, preferably with the MIG/MAG process.

Wear caused by abrasion from sand, silica, cement or carbon is the most frequent cause of system stoppages in many industries and is also the type of Hardfacing to be most carefully planned as the pieces do not wear uniformly: the intervention must also be done with different products on the same piece or with different thicknesses to obtain a uniform decay of the piece.

This category includes Hardfacing carried out on parts of machines or equipment subjected to abrasive and adhesive wear for the sliding of one metal on another, with or without the presence of seizures. Examples are the knives for cutting sheet metal, stamping dies, hammers and knives for disintegrator mills, the teeth of large gears, etc.

Performed on forging hammers, presses and hot shearers, punches and dies for the extrusion of tubes and, in general, processing equipment used for hot deformation of metals.

Erosion, cavitations, and corrosion, high pressure are other factors which determiner and may be present also in combination with the type of wear described above: in these cases interventions should be carried out with products different to those indicated. As the choice taken plays an important role in a company’s economy, we recommend the intervention of our Technical Service which will assist in dealing with problems of Hardfacing and will identify the product and the executive technology which is most suitable to the situation.