INCREASING THE FRETTING AND FATIGUE RESISTANCE OF Ti-6Al-4V THROUGH PLASMA PROCESSING IN NONAUTONOMOUS PLASMA GLOW

Titanium alloys possess unique combination of good mechanical properties and excellent corrosion resistance which make them an attractive material for application in marine engineering. Along with these properties there are some disadvantages. The most important of them is the low hardness and poor tribological properties, which leads to poor fretting and fatigue resistance.

These drawbacks limit the application of titanium alloys in production of machine parts, which are subjected to friction and surface contact loads. They can be successfully eliminated using numerous of surface treatment methods. One of the most commonly used is plasma treatment processes in nonautonomous plasma glow.

These methods usually include plasma thermochemical treatment and afterwards plasma spraying of large variety of materials to the surface of the treated sample, which will eliminate the drawbacks of the titanium alloys and will increase the area of their application in marine engineering. This article presents investigation of the results obtained from plasma nitriding and plasma spraying of titanium alloy Ti-6Al-4V in nonautonomous plasma glow using TiO2 powder.
The quality assessment and morphology of the plasma sprayed layer is made using micro structural analysis, EDS analysis, XRD analysis, SEM analysis and microhardness measurements.