Enhancing ductility and fatigue strength of additively manufactured metallic materials by preheating the build platform

Abstract

The effect of preheating the build platform (process) on the microstructure/defect structure (structure) as well as the tensile and fatigue behaviour (property) of the laser beam powder bed fused (LB‐PBF) 316L stainless steel (SS) is investigated. Preheating the build platform to 150°C (P150) affects the thermal gradient and cooling rate resulting in the reduction of the volumetric defects (i.e., gas‐entrapped pores and lack of fusion (LoF)) as compared with the condition where the build platform is non‐preheated (NP). The ductility of P150 LB‐PBF 316L SS is improved as compared with the NP counterpart, resulting from the less volumetric defects as well as the change in the crystallographic orientation of the grains in P150 condition. In addition, preheating the build platform is found to enhance the fatigue resistance of LB‐PBF 316L SS specimens. This is associated with fewer and smaller volumetric defects in P150 specimens as compared with the NP ones.

Document Details

Document Type
Pub Defense Publication
Publication Date
Nov 05, 2020
Source ID
10.1111/ffe.13372

Entities

People

  • Nam Phan
  • Nima Shamsaei
  • P.D. Nezhadfar

Organizations

  • Auburn University
  • Naval Air Systems Command

Tags

Fields of Study

  • Materials science

Readers

  • Combustion and Flow Dynamics.
  • Manufacturing Engineering.
  • Materials Science (Mechanical Engineering).

Technology Areas

  • Directed Energy