Formability, Microstructure and Properties of Inconel 718 Superalloy Fabricated by Selective Laser Melting Additive Manufacture Technology

Abstract

Many urgently needed inconel superalloy parts with complex internal cavity geometry and high surface precision are difficult to prepare by traditional subtractive manufacturing methods because of its poor machinability. The additive manufacturing technology that has emerged in recent years became a research hotspot in the manufacture of refractory and difficult-to-process metals. In the present study, selective laser melting (SLM), a typical additive manufacture technology, was used to prepare Inconel 718 samples. The influences of input laser energy density ((E, J/mm3) on densification behavior, phases composition, microstructures, microhardness, and wear performance of the SLM as-built Inconel 718 samples were explored in detail. X-ray diffraction (XRD), optical microscopy (OM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) were used to examine the phase composition and microstructure evolutions. The results show that the formablity, microstructures and mechanical properties of the printed samples were all improved with the increase of E within the parameter setting range of this study. At a lower E, the poor surface morphology and balling effect occurred, the density, hardness, and wear resistance were all at a relatively lower level. When an E value of 190 J/mm was properly set, the surface open-pores and balling effect disappeared, the laser scanning tracks became smooth and continuous, the near-full dense (99.15%) and specimens with good metallurgical bonding and no critical defect were obtained, in which the average microhardness value reached 348 HV0.2 and wear rate was 5.67 × 10−4 mm3/N·m. The homogeneity of the superalloy Inconel 718 was also explored.

Wear Analysis of Additively Manufactured Slipper-Retainer in the Axial Piston Pump

“…The test part (shown in Figure 2) was designed using CAD software (SolidWorks 2021, version number: 6.30.1030, Dassault Systèmes, Vélizy-Villacoublay, France) and manufactured using the SLM 125HL machine (SLM Solutions AG, Lubeck, Germany). There is also an additional factor that is very important in the case of hydraulic solutions, and at the same time, it is one of the biggest weaknesses of AM-the high surface roughness of the as-built parts [48][49][50][51][52][53][54]. In the case of H13 tool steel, Guenther et al [52] revealed that in the case of such steels, a direct correlation between surface roughness and friction coefficient, i.e., the rougher the surface was, the higher the friction force, does not take place.…”

Use Recognizable Digital twin in Virtual Measurement for General Both Evaluation of Additive & Subtractive Manufacturing Process

“…Dexel-based simulation allows modeling of additive manufacturing of different geometries by considering multi-axis machine kinematics and local process conditions. In 2021, Xiaoping Liu, Kuaishe Wang, Ping Hu, Xiaomei He, Baicheng Yan and Xuzhao Zhao [5], SLM is a typical additive manufacturing technology used to prepare parts with complex cavity geometry and high surface precision. In recent years, additive manufacturing technology has become a research hotspot in the manufacture of refractory and refractory metals.…”

Prediction of Epitaxial Grain Growth in Single-Track Laser Melting of IN718 Using Integrated Finite Element and Cellular Automaton Approach

“…SLM enables the rapid fabrication of both large and small parts with complex geometry with a high degree of precision and is used extensively throughout the aerospace, automotive, and medical fields nowadays. One of the most common nickel alloys used in SLM production is Inconel 718 (IN718), which has superior mechanical properties at elevated temperatures and is widely used to fabricate many critical components in the aerospace and aircraft engine industries [ 1 , 2 , 3 ].…”