Numerical and analytical investigation on meltpool temperature of laser-based powder bed fusion of IN718
Artikel i vetenskaplig tidskrift, 2021

Prediction of meltpool features in Laser-Based Powder Bed Fusion (LB-PBF) is a complex non-linear multiple phase dynamic problem. In this investigation, numerical simulations and analytical models are offered to predict meltpool temperature and to provide a methodology to estimate melt track quality. By determining the meltpool temperature, different rheological phenomena including recoil pressure can be controlled. Recoil pressure is known to drive the keyhole and conduction modes in LB-PBF which is an important factor to qualify the melt track. A numerical simulation was carried out using Discrete Element Method (DEM) with a range of process parameters and absorptivity ratios; allowing observation of the variation of meltpool temperature and free surface morphology, as calculated by the volume-of-fluid (VOF) method. A spatially thermophysical-based analytical model is developed to estimate meltpool temperature, based on LB-PBF process parameters and thermophysical properties of the material. These results are compared with experimentally observed meltpool depth for IN718 specimens and found to have a good accuracy. The numerical and analytic results show good agreement in the conduction mode to estimate the meltpool temperature and related phenomena such as recoil pressure to control the melt track and layering quality. The analytical model does not accurately predict the keyhole mode which may be explained by evaporation of chemical elements in the examined material.

Laser-based powder bed fusion

Numerical simulation

Conduction mode

Analytical model

Meltpool temperature

Keyhole mode

Författare

Mahyar Khorasani

Deakin University

RMIT University

Amir Hossein Ghasemi

Shahid Rajaee Teacher Training University

Martin Leary

RMIT University

William O'Neil

University of Cambridge

Ian Gibson

Universiteit Twente

Laura Cordova Gonzalez

Chalmers, Industri- och materialvetenskap, Material och tillverkning

Bernard Rolfe

Deakin University

International Journal of Heat and Mass Transfer

0017-9310 (ISSN)

Vol. 177 121477

Ämneskategorier

Teknisk mekanik

Annan materialteknik

Strömningsmekanik och akustik

DOI

10.1016/j.ijheatmasstransfer.2021.121477

Mer information

Senast uppdaterat

2021-07-01