Structure and properties of wear resistant layers fabricated by non-vacuum electron beam cladding

摘要

The non-vacuum electron beam cladding technology was used to increase wear resistance of commercially pure (CP) titanium by coating the titanium substrate with a powder mixture of boron carbide and titanium. The structure of samples was investigated by optical and scanning electron microscopy. Structural investigations revealed that fabricated materials consisted of three zones: a cladded layer, a heat affected zone and a titanium initial structure area. A thickness of the cladded layer depended on the treatment parameters and was equal to 1.2-1.4 mm. The main strengthening phases observed in the coatings were: titanium boride and titanium carbide particles. The aforementioned particles increased hardness and wear resistance of titanium. The maximum microhardness value of the coatings corresponded to a beam current of 27 mA. The data obtained were in a good correlation with the data of tribological tests. Wear resistance of the coatings was 1.85-fold higher than that of CP-titanium.