Comparison on Microstructure and Properties of Stainless Steel Layer Formed by Extreme High-Speed and Conventional Laser Melting Deposition

Abstract

A new technology named extreme high-speed laser melting deposition is presented in this paper. The deposition speed of this technology is as high as 30 m/min, which can promote the deposition efficiency from 0.09 to 0.54 m 2 /h. In addition, surface of EHLMD layer is smoother which can save part of the machining process after deposition and promotes the production efficiency by 6 times. AISI 431 martensitic stainless steel layers were fabricated on 27SiMn substrate by conventional laser melting deposition and extreme high speed laser melting deposition. The macroscopic morphology, microstructure, microhardness, and electrochemical corrosion resistance of the two kinds of layers were characterized. The results show that the microstructures of two kinds of layers comprise of martensite dendrite, retained austenite, and continuous inter-dendritic eutectic phases. Although results of the XRD test indicate that there are more retained austenite in the EHLMD layer, the microhardnesses of the two kinds of layers are basically the same, in the range of 600 to 720 HV. Corrosion resistance of the EHLMD layer is better than that of the LMD layer because of the higher Cr content and more uniform alloying elements distribution. Therefore, EHLMD can be considered as an effective alternative to electroplating and applied for production and repair of shaft parts in the manufacturing field.

Investigation of the Microstructure and Wear Properties of Conventional Laser Cladding and Ultra-High-Speed Laser Cladding Alloy Coatings for Wheel Materials

“…The results showed that the coating had higher wear resistance and resistance to RCF, far exceeding the substrate. Li et al [9] and Shen et al [10] prepared an AISI 431 alloy coating via the UHSLC process. The effect of laser cladding speed on the microstructure and corrosion resistance of the alloy coating was discussed and compared with the CLC alloy coating.…”

(Ti, Nb)(C, B)/IN625 In-Situ Reactive Coating Prepared by Ultra-High Speed Laser Cladding: Interfacial Characterization, Residual Stress and Surface Wear Mechanisms

“…Ultra-high-speed laser cladding (EHLA) has the advantages of high coating preparation efficiency [1], thin thickness [2], low dilution rate [3], high powder utilization [4], and high coating densities [5], which makes EHLA a green and advanced coating preparation technology with more potential than traditional laser cladding, and it has been popularized and applied in various industrial fields such as engineering machinery, aerospace, and so on [6,7].…”

Effects of sintering temperatures on the microstructure and mechanical properties of S390 powder metallurgy high-speed steel

“…The powder metallurgy process has the potential to eliminate the segregation of carbides, and the different consolidation techniques might be doing this, such as hot isostatic pressing (HIP) (Benito et al, 2021;Yang et al, 2021), spark plasma sintering (SPS) (Hu et al, 2022;Madej et al, 2022), and metal injection molding (MIM) (Herranz et al, 2017;Mukund and Hausnerova, 2020). In contrast to other PM processes, the SPS technique, in which temperature and uniaxial pressure are simultaneously applied to the powder, has the advantages of a short sintering time and a low sintering temperature, and the Joule heating effect and electric field effect caused by pulsed direct current accelerate the consolidation process (Zhang et al, 2017;Shen et al, 2019;Zeng et al, 2019;Shen et al, 2020).…”