Mechanical Performance of AlCrSiN and AlTiSiN Coatings on Inconel and Steel Substrates after Thermal Treatments

Abstract

The objective of this study was to explore the mechanical properties of AlCrSiN and AlTiSiN coatings deposited on Inconel and steel substrates after thermal treatments of 500 °C and 800 °C. Nanoindentation was used to measure the hardness and elastic modulus of the coatings, and microindentation was used for observing the contact damage with Hertzian contact loadings. Microscratch and Mercedes tests were used to evaluate the adhesive strength between coating and substrate with both progressive and static loads, respectively. The surface damage was inspected by optical microscopy and scanning electron microscopy (SEM). Focus ion beams (FIB) were used to mill the cross-sections in order to detect the extent and mode of failure. The results show that AlCrSiN coatings and Inconel substrates exhibit better mechanical performance, even after thermal treatments.

Comparative Study of Mechanical Performance of AlCrSiN Coating Deposited on WC-Co and cBN Hard Substrates

“…In the case of the cBN substrate, d is clearly present even for the smaller loads. As the load increases, more spa coating is observed, similar to previous research on similar materials[34,45,46…”

“…Calculation of adhesion energy followed the method from the previous study by S. J. Bull et al, and the values of G c were similar to previous research on similar coatings such as CrAlN and AlCrSiN [34,40,43,44]. Figure 5 presents the SEM images after the contact damage tests at a series of normal loads of 98 N, 196 N, and 294 N. For the sample of AlCrSiN coating deposited on the WC-Co substrate, the coating does not show any cracking.…”

“…et al, and the values of Gc wer previous research on similar coatings such as CrAlN and AlCrSiN[34,40,43,4 …”

“…For the WC-Co substrate, stick-slip deformation was induced via compressive stress and appeared at the contour. As the load increased, transverse cracks, which were induced by tensile stress, appeared until spallation of the coating occurred; this load is defined as the second critical load (L C2 ), implying failure of the interface between coating and substrate [34]. Interfacial failure occurred much earlier in the cBN substrate (seen in Figure 4b,c) with clear spallation of the coating [35,36].…”