Tribology of Si-rich TIG-deposited coatings on Zn–40Al–2Cu alloy

Abstract

The effect of Zn-40Al-2Cu-xSi (x = 4 and 8 wt-%) tungsten inert gas (TIG) surfaced coatings and multi-pass friction stir processing (FSP) on the tribological properties of Zn-40Al-2Cu alloy was studied. The coatings had a well-modified microstructure comprising of finely dispersed primary Si particles (Si P ). These particles act as in-situ reinforcements, improving coating resistance against the friction-induced strains applied during sliding wear. The results of dry sliding wear showed that, at the applied pressures of 0.25, 0.5, and 0.75 MPa, the wear resistance of 4-pass FSPed coatings containing 4 wt-% Si is higher than that of the base alloy by 27, 47, and 57%, respectively. This can be attributed to the substrate strengthening and formation of compacted tribolayers on the surface of FSPed samples.

Composite coating by TIG cladding with different rare earth oxides

“…The arc of TIG follows an overlapping path, as shown in Figure 1(a) so that a good MMC melt pool is created. The solidification is done through the conduction and convection mode of heat transfer [20] and a composite clad consisting of RE oxides and without RE oxide is created successfully. However, different samples with and without RE oxide vary in microstructure, nature and defects formed within and in the interfacial region.…”