Performance and evolution of W/steel joint fabricated by selective laser melting

Abstract

Herein, attempts were made to develop W/steel joints via selective laser melting (SLM) for the first time. The influence of processing parameters on the joint strength was investigated. To further improve the mechanical properties, we performed post-heat treatment on the asfabricated specimens. The results showed that large amounts of solid solution and dispersed micro-/nanoparticles appear in the interface of W/steel joints fabricated by direct SLM because of the uniqueness of non-equilibrium solidification, which is favourable for the bonding properties. However, the solid solution gradually transforms into the Fe 2 W(Ni, Cr) phase encapsulated with W particles during heat treatment, while the Fe 7 W 6 phase fills the poles at the W/steel interface, which is extremely detrimental to the bonding properties.