Compressive Behavior of 316L Stainless Steel Lattice Structures for Additive Manufacturing: Experimental...

Area of Science:

• Materials Science
• Mechanical Engineering
• Additive Manufacturing

Background:

• Lattice structures are vital for lightweight, load-bearing applications.
• Mechanical performance is sensitive to geometry, process parameters, and boundary conditions.

Purpose of the Study:

• Investigate compressive behavior of 316L stainless steel BCC lattices fabricated via LPBF.
• Analyze the influence of relative density and build orientation on mechanical properties.
• Validate experimental findings with finite element simulations.

Main Methods:

• Fabricated 316L stainless steel BCC lattices at four relative densities (20-80%) using LPBF.
• Performed quasi-static compression tests to determine elastic modulus, yield strength, and energy absorption.
• Utilized finite element simulations to model deformation, hardening, and boundary condition effects.

Main Results:

• Mechanical properties (elastic modulus, yield strength) strongly correlated with lattice density.
• Vertically built specimens exhibited slightly superior performance due to fewer processing defects.
• Simulations highlighted the impact of strut-joint rounding and the necessity of multi-cell models for accuracy, especially at low densities.

Conclusions:

• Density is a key factor in lattice mechanical performance, aligning with Gibson-Ashby scaling.
• Boundary conditions significantly affect stiffness predictions, particularly for single-cell models at low densities.
• The study provides a framework for accurate modeling and design of metallic lattices for various applications.