Microstructure and Corrosion Properties of Laser Cladding Fe-Based Alloy Coating on 27SiMn Steel Surface

Abstract

In this paper, the corrosion performance of a laser cladding Fe-based alloy coating on the surface of 27SiMn steel was studied. The Fe-based alloy coating was prepared on a 27SiMn steel surface by high-speed laser cladding. The microstructure, morphological characteristics, element content, and phase composition of the cladding layer were analyzed by an optical microscope (OM), scanning electron microscope (SEM), energy dispersive spectrometer (EDS), and X-ray diffractometer (XRD), respectively. The corrosion resistance of the 27SiMn substrate and Fe-based coating in different corrosive environments was tested through an electrochemical experimental station, a salt spray corrosion test box, and an immersion experiment. The Fe-based alloy cladding layer is mainly composed of a-Fe, M7C3, M2B, and Cr3Si. The cladding layer structure forms planar, cellular, dendrite, and equiaxed dendrite during rapid solidification. The corrosion potential of the cladding layer is higher than that of the substrate, and the arc radius of the cladding layer is larger than that of the substrate. After salt spray corrosion, a large number of red and black corrosion products appeared on the surface of the substrate; the surface of the cladding layer sample was still smooth, and the morphology was almost unchanged. The weight loss results of the cladding layer and 27SiMn matrix after 120 h of immersion are 0.0688 and 0.0993 g·cm−2, respectively. The weight loss of the cladding layer is 30.7% less than that of the matrix. Conclusion: Laser cladding an Fe-based alloy coating on the surface of 27SiMn has better corrosion resistance than the substrate, which improves the corrosion resistance of hydraulic supports.

A Fast Method of High-Frequency Induction Cladding Copper Alloy on Inner-Wall of Cylinder Based on Simulation and Experimental Study

“…Currently, although there have been relatively numerous studies focused on optimizing cladding structure and processes to enhance substrate performance, research on the induction melting cladding process of copper alloys on the inner walls of cylinders performance, research on the induction melting cladding process of copper alloys on the inner walls of cylinders remains relatively limited [8]. Common metallurgical bonding technologies between barrel substrates and claddings include overlay welding [9,10], thermal spraying [11,12], electric spark deposition [13,14], and laser cladding [15][16][17]. The study revealed that by conducting PTA welding on the surface of E32 steel, a surfacemodified cladding consisting of tungsten carbide reinforced cobalt was obtained.…”

Evolution of Non-Metallic Inclusions in 27SiMn Steel

“…27SiMn steel is a kind of low-alloy structural steel that is mainly used to manufacture hot stamping parts and is widely used in coal machinery, thermal power generation, geological drilling, and other fields [1]. Regarding the development of 27SiMn steel, a large number of previous studies have mainly concentrated on the 'steel after'.…”

Laser shock peening Fe-based coatings for enhancing wear and corrosion resistance

“…Zhu et al [9] performed laser melting carbon powder on the surface of U71Mn steel with purpose of improving the resistance to rolling fatigue wear. Fe-based self-fluxing coating was prepared on U71Mn steel, the average microhardness of the coating can reach 780 HV, which is significantly higher than that of the fusion zone and the substrate, meanwhile, no cracks in the coating were found even applied 453 kN static load on it [10]. The microhardness of the U71Mn steel was improved by 3.7 times by preparing Ni60-25%WC coating on it [11].…”