The erosion performance of cold spray deposited metal matrix composite coatings with subsequent friction stir processing

Abstract

This study forms an initial investigation into the development of SprayStir, an innovative processing technique for generating erosion resistant surface layers on a chosen substrate material. Tungsten carbide – cobalt chromium, chromium carbide – nickel chromium and aluminium oxide coatings were successfully cold spray deposited on AA5083 grade aluminium. In order to improve the deposition efficiency of the cold spray process, coatings were co-deposited with powdered AA5083 using a twin powder feed system that resulted in thick (>300 µm) composite coatings. The deposited coatings were subsequently friction stir processed to embed the particles in the substrate in order to generate a metal matrix composite (MMC) surface layer. The primary aim of this investigation was to examine the erosion performance of the SprayStirred surfaces and demonstrate the benefits of this novel process as a surface engineering technique. Volumetric analysis of the SprayStirred surfaces highlighted a drop of approx. 40% in the level of material loss when compared with the cold spray deposited coating prior to friction stir processing. Micro-hardness testing revealed that in the case of WC-CoCr reinforced coating, the hardness of the SprayStirred material exhibits an increase of approx. 540% over the unaltered substrate and 120% over the as-deposited composite coating. Microstructural examination demonstrated that the increase in the hardness of the MMC aligns with the improved dispersion of reinforcing particles throughout the aluminium matrix

Structure and corrosion behavior of cold-sprayed Cu/Ni composite coating post-treated by ultrasonic shot peening

“…1b, a depth-dependent gradient structure is formed on the USSPed Cu coating. Peat et al also reported that a similar gradient structure was obtained in the cold-sprayed WC-CoCr coating by the subsequent friction stir processing [30]. The cross section of the USSPed Cu coating can be divided into three zones: the top-most layer (about 50 μm depth) with dense structure, the intermediate layer (depth ranged from 50 μm to 100 μm) with some pores, and the internal layer with an original pore structure.…”

Post-Process Treatments on Supersonic Cold Sprayed Coatings: A Review

“…Coatings 2020, 10, 123 9 of 35 break up or dissolve the secondary phase particles in the cold sprayed metal matrix composite (MMC) deposits, leading to considerable improvement in mechanical properties. Incorporating cold spray with FSP is a novel two-stage surface engineering process referred to as 'SprayStir' [56,57]. Table 2 summarizes the previous studies regarding the effects of post FSP on cold sprayed coatings.…”

“…[59], with permission from © Elsevier); (b) general morphologies of as-sprayed SiCp/Al5056 coating after FSP at 600 rpm or 1400 rpm (adapted from reference [58],with permission from © Springer Nature); and (c) cross-section view of cold sprayed coating after FSP (adapted from reference [56], with permission from © Elsevier). [59], with permission from © Elsevier); (b) general morphologies of as-sprayed SiCp/Al5056 coating after FSP at 600 rpm or 1400 rpm (adapted from reference [58],with permission from © Springer Nature); and (c) cross-section view of cold sprayed coating after FSP (adapted from reference [56], with permission from © Elsevier). Huang et al [59] studied the grain structures within cold sprayed Cu-Zn alloy coatings before and after FSP via EBSD.…”

Cold Sprayed Tungsten Armor for Tokamak First Wall

“…Even then, the studies employing such concept are limited in the literature and involve successful depositions of W-Cu by Kang and Kang [10] and Deng et al [11], W-Ni-Fe by Xia et al [12], and low tungsten content in W-90Ta coatings by Barnett et al [13] only. Considering their excellent wear properties, a significantly broader series of studies involved the research of cemented carbides in a form of WC-Co [14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31], WC-Ni [32][33][34][35][36][37][38][39][40][41], WC-Co-Ni [42], WC-Co-Cr [31,[43][44][45], or WC-Cu-MoS 2 [46,47]. Unfortunately, the carbides could not be used for PFCs and so we could not built on these results.…”