Preliminary Process and Microstructure Examination of Flux-Cored Wire Arc Additive Manufactured 18Ni-12Co-4Mo-Ti Maraging Steel

Abstract

The production of large-size elements using additive manufacturing is a constantly evolving field that includes technological and material solutions. There is a need for a detailed analysis of the process and the products thus manufactured. In line with this trend, the flux-cored wire arc additive manufactured process and the part made of 18Ni-12Co-4Mo-Ti maraging steel were examined. The interpass temperature below 150 °C, the variation of the starting point and the gas flow of 12 L/min with a pre-flow of 2 s ensure the correct shape of the layers. The manufactured part underwent chemical composition analysis, macro- and microscopic examination and hardness measurements; in addition thermodynamic calculations were performed. The part is divided into a light-etched area (bottom part of the sample) with a hardness of 375 ± 12 HV10 and a dark-etched area (top part of the sample) with a hardness of 525 ± 11 HV10. Microscopic observations in the last layers showed supersaturated martensite with primary precipitates of μ-phase intermetallic compounds in intercellular spaces. In the earlier layers aging martensite with austenite and primary precipitates of intermetallic compounds were revealed. The share of austenite was 11.435 ± 1.313%.

Influence of in-situ process parameters, post heat treatment effects on microstructure and defects of additively manufactured maraging steel by laser powder bed fusion—A comprehensive review

“…Martensitic cellular structures or austenite on the cell borders might serve as 'bridges. 'for connection between the each and increase fracture resistance [69,[92][93][94][95][96][97]. The evolution of characteristics of maraging steel is greatly influenced by ageing.…”

“…Similarly, anchor rails, arresting hooks [123], and gimbal ring parts are used in aerospace [138] and aircraft applications [92]. Maraging steel is also used in defense-related applications like cannon recoil springs [93], and lightweight portable military bridges. Apart from this, maraging steel is used in applications like car parts (frames) , and atomic power plant parts like rotors, and shafts [94].…”

Indentation Plastometry for Study of Anisotropy and Inhomogeneity in Maraging Steel Produced by Laser Powder Bed Fusion

“…wide range. The advantages of WAAM, as applied to maraging steels, [1][2][3] largely relate to higher production rates, but the structure and surface finish tend to be relatively coarse, and the porosity level can be high. In general, the LPBF technique has been more popular than WAAM for maraging steels, [4][5][6][7][8][9][10] offering superior scope for geometrical and microstructural control.…”

On the Influence of Linear Energy/Heat Input Coefficient on Hardness and Weld Bead Geometry in Chromium-Rich Stringer GMAW Coatings

“…This problem is partially solved by the application of Fronius Cold Metal Transfer technology, nevertheless that technology is patented, expensive and excludes other current sources [ 31 , 32 , 33 , 34 ]. Another approach is to introduce an additional cooling subsystem [ 35 ], yet that can result in unwanted changes in the microstructure [ 36 , 37 ], although Reisgen et al reported that they observed no negative effects [ 38 ].…”