Application and Future Prospects of Thermal Spray SiC Coatings
Abstract
Thermally sprayed coatings allows to increase base surface functionality and add parameters,which base material did not had before. This feature opens the door to theapplication and design improvements in leading developments of aircraft, spacecraft, automotive,biomedical, marine and offshore industries. In this research, the main objectis thermally sprayed SiC coatings with modified SiC powder feedstock. Two differentpowder preparation techniques are compared in order to optimize the nano-layer, whichsurrounds and protects the spray powder. It allows thermally challenging particles couldreach the substrate surface without decomposing.The main scope of the work is to analyse how powder feedstock preparation techniqueinfluence end product properties. SiC coatings are sprayed with plasma thermal sprayinggun variating the spray properties. The XRD cross analysis of powder feedstock andSiC coatings were conducted, revealing, that SiC particles are delivered to the substrateresulting in high crystallinity of SiC particles.Afterwards, the thermal oxidation tests in TGA device were carried out. The weightloss after 30 min holding in 1200C, showed 6.5% to 8.5% weight loss. Tribological testswere carried out in three different conditions, with 440C stainless steel, WC-Co and SiCcarbide counterparts. Morphology of the coatings were analysed with SEM, EDS andConfocal microscopy. Some of the test results, especially in regards of chemical analysis,are protected by confidentiality agreement with Seram Coatings AS .