Effect of Homogenization Heat Treatment on the Evolution of Carbonitrides in Powder Bed Fusion Processed INCONEL 718

Published

June 9, 2025

Author(s)

Selda Nayir, Max Bertrand, Andrew Iams, Simon Perusin, James Zuback, Lucille Giannuzzi, Fan Zhang

Abstract

Inconel 718 fabricated using laser powder-bed fusion often contains precipitates in the as-built condition that can be grown or dissolved by high-temperature heat treatments depending on the combination of temperature and time. In this study, two homogenization heat treatment regimens were applied to discern the impact of heat treatment conditions on the growth of complex M(C, N) carbonitrides. In the first heat treatment, the samples underwent heat treatment between 1050 ˚C and 1200 ˚C for 0.5 h. In the second heat treatment, the samples were held at a constant temperature of 1150 ˚C, with varied holding times from 0.5 h to 8 h. The observed secondary phases included Laves phase and carbonitrides enriched with Nb, Ti, Mo, and Al-rich oxides. Heat treatments dissolved some of the secondary phases, but the carbonitrides persisted in the structure regardless of temperature and duration. Changes in the compositions, lattice parameters, and sizes of M(C, N) carbonitrides were measured using transmission electron microscopy and high-energy synchrotron X-ray diffraction. The results offer a quantitative understanding of the Nb enrichment in carbides and their coarsening with elevated temperatures and extended holding times.

Citation

Materials Characterization

Volume

227

Pub Type

Journals

Download Paper

https://doi.org/10.1016/j.matchar.2025.115271

Local Download

Keywords

IN178, Laser Powder bed fusion, homogenization, carbonitride, carbides

Citation

Nayir, S. , Bertrand, M. , Iams, A. , Perusin, S. , Zuback, J. , Giannuzzi, L. and Zhang, F. (2025), Effect of Homogenization Heat Treatment on the Evolution of Carbonitrides in Powder Bed Fusion Processed INCONEL 718, Materials Characterization, [online], https://doi.org/10.1016/j.matchar.2025.115271, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=957106 (Accessed February 14, 2026)