Characterization of Wear Resistance and Corrosion Resistance of Plasma Paste Borided Layers Produced on Pure Titanium.

Abstract

Commercially pure titanium was plasma paste borided using various temperatures of the process. An increase in the boriding temperature resulted in an increase in the thickness of the borided layer. All the layers produced consisted of an outer compact TiB2 zone and an inner TiB zone in the form of whiskers penetrating into the substrate. The presence of hard titanium borides resulted in a significant increase in wear resistance compared to non-borided pure titanium. However, the thickness of the layer produced strongly influenced the wear behavior, in respect of the time required for complete destruction of the layer. Higher wear resistance was characteristic of the TiB2 layer due to its compact nature, whereas the specific morphology of TiB whiskers resulted in their lower wear resistance compared to the outer TiB2 layer. Plasma paste boriding of pure titanium also had an advantageous effect on corrosion resistance compared to non-borided pure titanium. Simultaneously, due to the higher thickness of TiB2 layer, the specimen borided at a higher temperature showed higher corrosion resistance.