Laser cladding is a technology that uses high-energy-density lasers to quickly melt and solidify alloy powder on the surface of the metal substrate to form a cladding layer with good performance. Especially, martensitic stainless steel is widely used as a cladding material due to its high hardness and wear resistance. In this work, the martensitic stainless steel layers were fabricated on the C45 steel substrate by the laser cladding with different process parameters. The results show that holes in the cladding layer is unavoidable. The laser cladding process parameters have the important influence on the residual stress in the cladding layer. Under the action of residual stresses, the holes in the cladding layer will be the source of cracks, which will cause cracks in the cladding layer.

This paper aims to clarify the development and characterization of cold-sprayed aluminum coatings on a non-regular medium-carbon steel surface. The work is carried out with a two-fold purpose: to optimize the deposition process and coating thickness and to learn how substrate defects and imperfections influence coating performance and the corrosion resistance of the coated material.

This paper presents research results showing how spraying distance affects the bonding strength, porosity, microhardness, and deposition efficiency of HVOF-sprayed NiCrAl coatings. The coatings examined were deposited on quenched 1045 steel substrates at spraying distances of 340, 360, and 380 mm. At the optimal standoff distance of 360 mm with kerosene and oxygen flow rates at 22 L/h and 850 L/min, respectively, NiCrAl coatings were achieved with a bonding strength of 66 MPa, microhardness of 418.56 HV 0.3 , porosity of 1.1%, and deposition efficiency of 65.3%.

Thermal spraying technologies take part in the current worldwide scene as serviceable and profitable technologies for a wide range of intents. The growing adoption of those techniques has driven companies to progressive investments in efforts to reach innovative designs and market needs. Wear resistance is among the desired features which certain components must be able to provide while performing. In this context tribology has an outstanding importance, where the adoption of suitable materials and operational parameters jointly contribute for a longer lifetime of parts. This contribution presents a comparison of AISI 1045 (DIN C45) steel surfaces coated by means of arc spray process, employing cored wires as feedstock. Corresponding light microscopy, SEM-EDX, 3Dprofilometry, hardness and ball-on-disk analyses were conducted to understand the tribological behaviour of two unlubricated iron-based layers with and without carbides reinforcement. The results point out equivalent thickness, porosity and as-sprayed roughness for both coatings. Higher hardness and lower friction coefficients for the carbide free coating as well as a downward trend considering the coefficients of friction for coated and uncoated surfaces under heavier loads.

Fatigue strength and fracture mechanism of a medium carbon steel with HVOF thermally sprayed WC-Co coatings were investigated under rotating bending. Two types of commercially available WC-Co powders were used, which have similar total chemical composition with different manufacturing processes. The fatigue strengths of the specimens with thick coatings were lower than that with thinner ones. Especially, it was found that the fatigue strengths of the thick coating specimens decreased more greatly than that of the grit blasted ones. Also, the morphology of the fatigue crack depended on the type of powders and the thickness of the coating. Futhermore, an embedded Al 2 O 3 grit and a crack generated during the grit blasting were found near the fatigue fracture origin of the coated substrate.