Development of localised process parameter control for repeatability in metal additive manufacturing
Citation:
Dowling, Luke Patrick, Development of localised process parameter control for repeatability in metal additive manufacturing, Trinity College Dublin.School of Engineering, 2021Download Item:
Abstract:
Due to the many advantages associated with metal additive manufacturing (AM)
processes, research into these technologies has grown significantly over recent years.
However, repeatability and reproducibility are critical issues in AM when compared to
traditional manufacturing processes.
The overall aim of this project was to comprehensively investigate the sources of this
repeatability issue and to develop a means of improving the process repeatability. This
was achieved by a thorough literature review with an in-depth focus on the
configuration present in the ProX DMP 200.
The causes and impact of repeatability were reviewed at three stages of the AM
process: pre-process, para-process and post-process. It was found that the most
impactful effect for repeatability is non-uniform energy density in the build area. This
was predominantly due to errors associated with the F-Theta lens, plume absorption
and the effect of angle of incidence on the powder bed.
A new energy density equation was developed to account for the spatially varying
energy density in selective laser melting. This equation was used as a basis for
location-dependent control of process parameters. These adapted parameters were
tested using samples made of cobalt chrome alloy and 316L stainless steel.
The adapted parameters reduced the range of variation in local mechanical property
values by up to 40%, representing a statistically significant reduction in the systematic
variation between the centre and edge of the machine?s working envelope.
Sponsor
Grant Number
European Union (EU)
Aerialist (Project ID: 723367 Funded under: H2020-EU.3.4. ? SOCIETAL CHALLENGES ? Smart, Green And Integrated Transport)
Author's Homepage:
https://tcdlocalportal.tcd.ie/pls/EnterApex/f?p=800:71:0::::P71_USERNAME:DOWLINLUDescription:
APPROVED
Author: Dowling, Luke Patrick
Advisor:
Trimble, DanielFlorea, Larisa
Publisher:
Trinity College Dublin. School of Engineering. Discipline of Mechanical & Manuf. EngType of material:
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