Effect of the scanning strategy and tribological conditions on the wear resistance of IN718 obtained by Laser Metal Deposition

Effect of the elevated temperature on the wear behavior of Laser Metal Deposition IN718 repairs

“…This result is in contradiction with the literature [10]. However, this has already been explained in a previous publication dedicated to room temperature tests [7]. In fact, the lack of influence of the repair strategy on their wear volume is mainly due to the surface nature of the contact (flat-on-flat, large contact area, compared to the size of microstructural characteristics), which erases the heterogeneities in surface mechanical properties.…”

“…The results obtained at elevated temperatures for different normal forces are compared to those obtained at room temperature. However, since the wear behavior at room temperature of this material deposited by LMD under these same tribological conditions has already been addressed in a previous publication [7], one can briefly summarize that the main wear mechanisms are primarily abrasion and adhesion. It is also worth noting that the microstructures of the repairs are greatly different from the IN718 conventionally manufactured.…”

“…The wear behavior of IN718 repaired by LMD has not been extensively studied in the literature and in the case of sliding wear, most of the studies have been conducted at room temperature. In a previous author's work, it has been shown that, at room temperature, the scanning strategy and the sliding direction according to the bead orientation do not impact the wear behavior of the IN718 LMD repairs [7]. As the number of cycles increases, the wear volume tends to stabilize because of the appearance of an oxidized layer that protects the repairs and wears the metallic counter body.…”

“…The latter is depicted in Figure 2. The latter is the same bench used for the study of the wear resistance of the IN718 LMD repairs at room temperature with the addition of a heating system [7]. It includes a fixed arm that carries the tangential force sensor and the counterbody.…”

“…Recently, Lui et al showed also the importance of heat treatments on the wear resistance of this alloy deposited by LMD [8] and they observed an anisotropic behavior of wear properties depending on the tribologically loaded surfaces. The detrimental impact of Laves phases has also been highlighted [7], [8]. Still at room temperature, Xu et al showed that, by optimizing process parameters, it was possible to improve the wear resistance of as-built LMD parts [9].…”