Characterisation of biomedical titanium layers deposited by a vacuum plasma spray process

Abstract

In this paper we will describe the process of the deposition of thick layers of VPS-Ti coating, which is used as a bonding layer for the upper porous Ti coatings on implant substrates. In order to deposit the powder, we used HoGANaS Ti powder labelled as AMPERIT 154.086-63 mu m. In order to test the mechanical properties and microstructure of the VPS-Ti coating, the powder was deposited on C 4171 (X15Cr13 EN10027) steel substrates. Mechanical tests of the microhardness of the coating were per-formed by the Vickers hardness test method (HV0.3) and tensile strength by measuring the force per unit area (MPa). The micro-hardness of the coating is 159 HV0.3, which is consistent with the microstructure. The coating was found to have a good bond strength of 68 MPa. The morphology of the powder particles was examined on a scanning electron microscope. The microstructure of the coating, both when deposited and etched, was examined with an optical microscope and a scanning elec-tron microscope. By etching the coating layers, it was found that the structure is homogeneous and that it consists of a mixture of low-temperature and high-temperature titanium phases (alpha-Ti + beta-Ti). Our tests have shown that the deposited layers of Ti coating can be used as a bonding layer for porous Ti coatings in the production of implants.