Search Results (2)

Improving the wear resistance and corrosion resistance of 60Si2Mn steel is an important issue in agricultural machinery. A Rockit 606 coating layer may exhibit excellent performance in wear resistance and corrosion resistance. However, there are very a few public reports and articles involving the topic of a Rockit 606 laser cladding layer on a steel 60Si2Mn surface. It is of great importance to research Rockit 606 laser cladding layers. This work focuses on studying the microstructure and properties of Rockit 606 coating layers with different scanning speeds by disk laser cladding. Firstly, the laser cladding platform was designed and set up. Secondly, the laser cladding parameters were designed, and then the laser cladding experiment was conducted, and the Rockit 606 coating layers were obtained. And finally, the microstructure, phase distribution, corrosion resistance, surface hardness, and wear resistance of the coating layers were measured and analyzed. A scanning electron microscope (SEM), X-ray diffractometer (XRD), electrochemical workstation, and microhardness tester were used in this work. It was found that the microstructure Rockit 606 alloy coating consists of γ-Fe, V₈C₇, and Cr₇C₃. The microhardness of the Rockit 606 alloy coatings decreased with an increase in the scanning speed. When the scanning speed was 4 mm/s, the highest microhardness value reached 867.2 HV, which is about three times of that of the substrate. The average coefficients of friction (COFs) of the coatings decreased with an increase in the scanning speed, which led to the corresponding decrease of the wear rate. When the scanning speed was 4 mm/s, the wear behavior of the coating was mainly oxidative wear and a small amount of adhesive wear. The self-corrosion current density of the coatings prepared by laser cladding in a 3.5 wt.% NaCl solution is one order of magnitude lower than that of the substrate, indicating that the coatings have better corrosion resistance properties. Full article

Additive manufacturing with multi-material design offers great possibilities for lightweight and function-integrated components. A process chain was developed in which hybrid steel–steel-components with high fatigue strength were produced. For this, a material combination of stainless powder material Rockit^® (0.52 wt.% C, 0.9% Si, 14% Cr, 0.4% Mo, 1.8% Ni, 1.2% V, bal. Fe) cladded onto ASTM A572 mild steel by plasma arc powder deposition welding was investigated. Extensive material characterization has shown that defect-free claddings can be produced by carefully adjusting the welding process. With a tailored heat treatment strategy and machining of the semi-finished products, bearing washers for a thrust cylindrical roller bearing were produced. These washers showed a longer fatigue life than previously produced bearing washers with AISI 52100 bearing steel as cladding. It was also remarkable that the service life with the Rockit^® cladding material was longer than that of conventional monolithic AISI 52100 washers. This was reached through a favourable microstructure with finely distributed vanadium and chromium carbides in a martensitic matrix as well as the presence of compressive residual stresses, which are largely retained even after testing. The potential for further enhancement of the cladding performance through Tailored Forming was investigated in compression and forging tests and was found to be limited due to low forming capacity of the material. Full article