J. Mater. Sci. Technol.

Special Issue: 增材制造/3D打印专辑

• Orginal Article •    

Microstructure and Fracture Behavior of 316L Austenitic Stainless Steel Produced by Selective Laser Melting

Casati R.(),Lemke J.,Vedani M.   

  1. Department of Mechanical Engineering, Politecnico di Milano, Via La Masa 34, Milano, Italy
  • Received:2016-03-23 Accepted:2016-06-15 Published:2016-08-10 Online:2016-10-10
  • Contact: Casati R.

Abstract:

Selective laser melting is an additive manufacturing method based on local melting of a metal powder bed by a high power laser beam. Fast laser scans are responsible for severe thermal gradients and high cooling rates which produce complex hydrodynamic fluid flow. These phenomena affect crystal growth and orientation and are believed to be the cause of material spattering and microstructural defects, e.g. pores and incompletely melted particles. In this work, the microstructure and texture of 316L bars built along two different orientations and the effect of different distribution of defects on their mechanical response and failure mechanisms were investigated. Partially molten powder particles are believed to be responsible for the scattering in elongation to failure, reduced strength, and premature failure of vertical samples.

Key words: AISI 316L, Additive manufacturing, Selective laser melting, Microstructural analysis, Fracture behavior