APPLICATION OF INFRARED THERMOGRAPHY TO THE DAMAGE IDENTIFICATION IN A COLD-SPRAYED COPPER COATING

The work focuses on a cold-sprayed copper coating generated on a PEEK substrate. The main methodology to analyse pre-existing defects and damages generated during loading is infrared thermography. Pulsed thermography, used as a non-destructive technique, allows identifying defects generated due to the manufacturing process in terms of position and size (0.04-1.04 mm2); they were detected also by SEM images, underlying decohesive cracking and delamination. Besides, thermographic monitoring during the static tensile tests allows estimating the damage initiation stress σD equal to 17.4 MPa for the coating. Eventually, from the mechanical output and thermal monitoring, it was possible to estimate ECu = 43930 MPa and UTSCu=78.6 MPa. Hence, these thermographic applications are efficient tools to characterize cold-sprayed coatings, understand their mechanical performances and support the design of functionalized components