Atomistic study on cooling rate induced nanoindentation properties of Additively Manufactured Inconel-718

TL;DR

This study uses atomistic simulations to investigate how different cooling rates during additive manufacturing influence the nanoindentation properties of Inconel-718, revealing key insights into its nanomechanical behavior.

Contribution

It introduces an atomistic simulation approach to analyze the impact of cooling rates on the nanoindentation response of AM Inconel-718, a novel investigation in this context.

Findings

Cooling rate significantly affects hardness and dislocation density.

Higher cooling rates lead to increased surface imprint depth.

Microstructure evolution correlates with mechanical response.

Abstract

Inconel-718's compatibility with additive manufacturing (AM) has made it a center of attention for researchers. This paper focuses on how cooling rates affect the hardness of AM Inconel-718. To study the AM process, monocrystalline and polycrystalline Inconel-718 layers were added to a pristine substrate and equilibrated at 2000 K before being cooled to 300 K using cooling rates ranging from 5 K/ps to 100 K/ps, as well as an exponential cooling rate. The layers were then subjected to atomistic nanoindentation simulation to analyze the nanomechanical response, including hardness, dislocation density, microstructure, and surface imprints, at different cooling rates. Load-displacement (P-h) curves were plotted for each cooling rate. The findings of this study provide crucial insights into the effect of cooling rate on the nanoindentation-based response of additively manufactured Inconel-718. These insights can aid in the design of high-performance components for various applications