Multipart Build Effects on Temperature and Residual Stress by Laser Beam Powder Bed Fusion Additive Manufacturing.

Area of Science:

• Materials Science
• Mechanical Engineering
• Manufacturing Processes

Background:

• Laser beam powder bed fusion (PBF-LB) is a key metal additive manufacturing (AM) technology with aerospace and medical applications.
• Current PBF-LB process modeling often focuses on single-part builds, not reflecting practical multi-part manufacturing scenarios.
• The impact of batch size on the thermal and mechanical behavior of additively manufactured components remains under-investigated.

Purpose of the Study:

• To propose and validate a novel thermomechanical modeling framework for multi-part PBF-LB.
• To computationally investigate the influence of batch size (number of components) on temperature and residual stress (RS).
• To provide insights for optimizing PBF-LB printing strategies to minimize RS in manufactured parts.

Main Methods:

• Development of a first-of-its-kind thermomechanical modeling framework for multi-part PBF-LB.
• Computational simulation of PBF-LB processes with varying sample numbers (1, 2, and 4 components).
• Analysis of temperature evolution and residual stress distribution within part-scale components.

Main Results:

• Residual stress (RS) within parts was found to decrease as the number of components per build increased.
• Components situated in the central regions of the build plate exhibited higher RS compared to those at the borders.
• A clear correlation between batch size and the resulting residual stress was computationally demonstrated.

Conclusions:

• The number of components in a PBF-LB build significantly affects the resulting residual stress.
• Optimizing the arrangement and number of parts on the build plate can mitigate residual stress.
• Findings offer practical guidance for AM designers and operators to enhance PBF-LB manufacturing efficiency and part quality.