Abstract | The effect of interstitials on the yield strength, elongation, hardness and fatigue properties has been widely reported for dense titanium and titanium alloys. Nitrogen has generally the most significant effect followed by oxygen and carbon. While nitrogen and carbon are usually not found at high concentrations in dense titanium, oxygen is a common contaminant due to the high affinity of titanium for oxygen and the high solubility of oxygen in titanium. Titanium powders are currently used for the production of dense and porous components using different processes such as compaction, cold or hot isostatic pressing, powder injection molding (PIM) as well as innovative foaming processes. The initial powder characteristics (surface area), the process parameters (time, temperature) and environment (atmosphere, binder, support) may have a significant impact on the component final oxygen content. It is, therefore, important to identify and control the various sources of oxygen. This paper reviews the sources of oxygen contamination when processing titanium powders. The effect of oxygen will be discussed using experimental results in the context of two specific processes Ti-PIM and Ti-Foam. |
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