This study focuses on new technologies for the production of medical implants using a combination of robotics and microplasma coatings. This involves robot assisted microplasma spraying (MPS) of a multilayer surface structure on a biomedical implant. The robot motion design provides a consistent and customised plasma coating operation. Based on the analytical model results, certain spraying modes were chosen to form the optimised composition and structure of the titanium/hydroxyapatite (HA) multilayer coatings. It is desirable that the Ti coated lower layer offer a dense layer to provide the implant with suitable structural integrity and the Ti porous layer and HA top layer present biocompatible layers which are suitable for implant and tissue integration. Scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD) were used to analyse the structure of the coatings. The new robot assisted MPS technique resulting from this research provides a promising solution for medical implant technology.
Hydroxyapatite (HA) has become a widely used material for bone grafting and surface modification of titanium-based orthopedic implants due to its excellent biocompatibility. Among various coating techniques, microplasma spraying (MPS) has gained significant industrial relevance. However, the clinical success of HA coatings also depends on their adhesion to the implant substrate. Achieving durable fixation and reliable biological integration of orthopedic implants remains a major challenge due to insufficient coating adhesion and limited osseointegration. This study addresses challenges in dental and orthopedic implantology by evaluating the microstructure, mechanical properties, and biological behavior of bilayer coatings composed of a zirconium (Zr) sublayer and an HA top layer, applied via MPS onto titanium alloy. Surface roughness, porosity, and adhesion were characterized, and pull-off and shear tests were used to assess mechanical performance. In vitro biocompatibility was tested using rat mesenchymal stem cells (MSCs) to model osteointegration. The results showed that the MPS-fabricated Zr–HA bilayer coatings achieved a pull-off strength of 28.0 ± 4.2 MPa and a shear strength of 32.3 ± 3.2 MPa, exceeding standard requirements. Biologically, the HA top layer promoted a 45% increase in MSC proliferation over three days compared to the uncoated titanium substrate. Antibacterial testing also revealed suppression of E. coli growth after 14 h. These findings support the potential of MPS-applied Zr-HA coatings to enhance both the mechanical integrity and biological performance of titanium-based orthopedic implants.
The paper describes the main technological approaches for manufacturing medical implants from titanium alloy using Computer Numerical Control (CNC) machines and microplasma spraying of hydroxyapatite (HA) coatings. New approaches to the formation of coatings with the desired structure and properties and the challenges of developing the technologies for producing modified implants are discussed.
1 January 2022 in Ukrainian journal of mechanical engineering and materials science
The purpose of this work is to justify the feasibility of using the technology of microplasma sputtering from wire materials to obtain porous coatings for biomedical purposes, the modulus of elasticity of which is close to the corresponding characteristic of human cortical bone tissue. Analyzed the influence of the technological parameters of the microplasma sputtering regime on the degree of porosity of the coating. As a result, it was found that a decrease in current strength and consumption of plasma-forming gas, as well as a decrease in the speed of feeding the sprayed wire into the plasma jet lead to an increase in the porosity of the coatings. Even though these parameters are interrelated, for each individual material are limited by certain limit values, in case of nonobservance of which the stable process of melting and dispersion of the sprayed wire in the plasma jet becomes impossible. Established the limit parameters of the microplasma sputtering process for titanium alloy VT1-00 and zirconium alloy KTC-110, which allows obtaining a coating with maximum porosity. Conducted studies of the adhesion strength of the obtained coatings, formed through a low-porous sublayer, with the maximum degree of porosity according to the ASTM C633- 13 (2017) method which proven that the indicators of the adhesion strength of the coatings to the VT6 titanium alloy base at normal separation meet the requirements of the international quality standard ISO 13179- 1:2021.
1 July 2025 in Advances in Science and Technology Research Journal
The work is devoted to studying the technological capabilities of the processes of microplasma spraying of wires from heat-resistant nickel alloy Inconel 82 with further laser melting of the sprayed layers to produce narrow-path coatings during restoration of worn end faces of ribbed parts, used...