This study assesses the erosive wear performance of hard-phase-reinforced coatings developed for use on hammer drills employed in mining operations. Several laser-clad coatings consisting of a nickel matrix with various tungsten carbides were evaluated along with two Fe-based alloys, FeCrBSi and FeCrNiBSi, and a WC-CoCr reference layer deposited by HVOF spraying. Erosion tests were conducted in 15° steps up to an angle of 90° and coating performance was determined based on volume loss obtained by 3D profilometry. At low angles, the more brittle materials lost significantly less volume, but at 90°, wear-resistant steel performs almost as well as a hard-phase loaded coating. Laser-clad layers with spherical fused tungsten carbides (FTC) performed better overall than coatings with regular (angular) FTC.

This work evaluates an in-mold spraying process for the production of injection molded plastic parts with integrated Cu pathways. Prior to injection, Cu is cold sprayed on mold insert surfaces, forming a metal layer that is subsequently transferred to the plastic part. The success of the process hinges on the bond strength of the Cu to the mold, which depends on surface conditions, mold material, and spray parameters. In this study, Cu powder is cold sprayed on carbon tool steel coupons prepared by grit blasting using different grit sizes. The coupons were sprayed at longer stand-off distances using lower gas flow rates than usual to reduce particle impact velocity and thus bonding strength. Coating cross-sections were examined and surface roughness, bond strength, and residual stress were measured. The results show that bond strength varies almost linearly with root-mean-square surface roughness, R∆q, and that reducing line distance or scanning step size can improve the transferability of the Cu layer.

Magnesium and magnesium alloys are the lightest structural materials with an approximate density of 1.7 g/cm³ (density of aluminium ~2.7 g/cm³). Due to the poor corrosion and wear resistance properties, they need to be coated for usage in lightweight constructions. AlSi20 was found to be a suitable coating material to improve the properties of parts made of the magnesium alloy AZ31B. Within this work, coatings are applied by thermal spraying, laser cladding and the combination of both processes. These coatings were investigated regarding corrosion protection in 3.5 % chlorine solution in a three electrode setup to obtain electrochemical corrosion characteristics. Abrasive wear was investigated using a pin-on-disc tribometer and abrasion rate was calculated. Resistance against shock loads was tested by applying a cyclic load at 50 Hz in order to investigate the resistance against impact stresses.

Zinc coatings are widely adopted for cathodic corrosion protection. Mostly the process of choice is hot-dip galvanizing but due to limitations regarding component size and composition of the galvanizing bath it is not always practicable. In the present paper zinc coatings alloyed with Al, Sn, Mg and Cr are applied by twin wire arc spraying to enhance the corrosion protection ability of zinc thermal sprayed coatings. The alloys were characterized and investigated using salt spray test and by means of electrochemical corrosion. Corrosion damage and products were investigated by optical microscopy, scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDS) and electron probe microanalysis (EPMA).