Enhancing Inconel 718 Superalloy Properties Through SLM and Boronizing Techniques

Inconel 718 is a nickel-based superalloy renowned for its high strength, corrosion resistance, and thermal stability, making it ideal for aerospace, energy, and high-performance applications. This study investigates the effects of boronizing and boraluminizing on Inconel 718 produced via the Selective Laser Melting (SLM) process. Boronizing, a thermochemical surface treatment, improves surface hardness by diffusing boron into the alloy, while boraluminizing introduces both boron and aluminum, offering potential enhancements in wear and corrosion resistance.
In this research, two boronizing treatments and one boraluminizing treatment were applied under varying heat treatment times. The effects of these surface modifications on microstructure, coating thickness, wear resistance, corrosion behavior, and microhardness were examined using Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), Energy Dispersive Spectroscopy (EDS), microhardness tests, wear tests, and corrosion tests.
Results showed that the boraluminized sample exhibited the highest hardness (2148 HV) and lowest wear loss, while both boronizing and boraluminizing treatments improved corrosion resistance compared to untreated samples. Additionally, boraluminizing resulted in the formation of a protective oxide layer over time, further enhancing corrosion resistance. These findings suggest that boronizing and boraluminizing significantly extend the service life of Inconel 718 by improving its surface properties, particularly in high-temperature and corrosive environments. This research offers crucial insights for optimizing surface treatments, making Inconel 718 even more robust for high-stress applications, particularly in aerospace and energy sectors.