Thermohydrogen Processing of 3D Screen Printed Titanium Parts

The present study addresses the need for grain refinement in free sintered titanium alloys produced by 3D screen printing. Thermohydrogen processing (THP) was used for temporary alloying Ti-6Al-4V with hydrogen to refine its microstructure. The impact on microstructure was investigated by a parameter study with varying temperatures, exposure times and hydrogen partial pressures. Heat treated specimens were examined by optical microscopy, XRD and thermal analysis. The influence of the refined microstructure on the mechanical properties was evaluated by tensile and microhardness testing. Ultrafine grained microstructures with ultimate tensile strengths of up to more than 1000 MPa could be produced.