Fundamental Understanding of the Dissolution of Oxide Film on Ti Powder and the Unique Scavenging Feature by LaB6

The surface oxide film on Ti powder consists of TiO2, Ti2O3, and TiO and starts to dissolve into the titanium matrix underneath from similar to 943 K (670 A degrees C). LaB6 can scavenge O prior to the active dissolution of the surface oxide film. The scavenging process begins by forming an interfacial LaBO3 layer due to reaction between surface oxide layer and LaB6, followed by diffusion of oxygen through the LaBO3 layer. The unique oxygen-scavenging feature of LaB6 produces better tensile elongation. (C) The Minerals, Metals & Materials Society and ASM International 2017