WHAT IS VANADIZING?
Vanadizing is a thermochemical treatment in which Vanadium atoms are spread on the surface of the workpiece to form carbides with the base material.
Two compounds are formed:
High hardness 2000-3000 HV on carbon and alloyed steels.
To further improve mechanical properties, the parts can be tempered after vanadizing. Vanadizing increases the resistance to acids, especially organic acids and alkalis.
A wide variety of ferrous, superalloy and sintered materials can be treated.
Increases component life.
Increases the stain resistance of components.
Provides good resistance to abrasive, sliding and adhesive wear.
Reduces the need for lubrication.
Has a low coefficient of friction.
Vanadizing reduces the tendency to cold weld.
PROPERTIES OF THE VANADIZED LAYER
The hardness of the Vanadized layer in carbon steels far exceeds that of galvanic chromium and traditional heat treatments, case-hardening, carbonitriding, nitriding.
The hardness of the Vanadized layer varies from 200 to 3000 HV depending on the base material used. The thickness of the Vanadized layer can vary from 0.003 mm to 0.007 mm depending on the base material and applications.
RESISTANCE TO ACIDS
Vanadizing increases resistance to sulphuric and hydrochloric acids and to organic acids in general. It gives the Vanadized components high stain-resistance characteristics both to atmospheric agents and to oils and fuels.
The parts to be treated are placed in intimate contact with the vanadizing product and placed in the oven. The parts are brought to a temperature of 1050°C in a protective atmosphere.
The time in temperature depends on the material and on the required Chrome-plating depth. The time varies between 6 – 15 h.
The increase in volume is generally from 5% to 7% of the Vanadized layer; it varies according to the base material, but is preferable and available for a given geometry and treatment cycle.