Dependence of the elasticity modulus of microplasma coatings made of titanium grade VT1-00 and zirconium grade KTC-110 on their porosity

A Brief Review of Current Trends in the Additive Manufacturing of Orthopedic Implants with Thermal Plasma-Sprayed Coatings to Improve the Implant Surface Biocompatibility

“…Thus, it can be concluded that varying the MPS parameters makes it possible to obtain coatings with predictable porosity from titanium, zirconium, and hydroxyapatite, but the process of choosing the deposition parameters is still semi-empirical. This state of affairs, on the one hand, shows the prospect of developing a mathematical model of the process and establishing the relationship between the parameters of the MPS and the porosity of the coating, while on the other hand, it increases the value of the practical recommendations presented in the papers [14,16,17,84,96]. It must be said that at present there has not been a systematic study for MPS of tantalum wire; so far only preliminary results have been obtained on MPS of tantalum on an elbow joint endoprosthesis made of a titanium alloy on a CNC machine, as well as the finding that the microhardness of a microplasma tantalum coating (702.3 ± 80 HV) is on average two times higher than that of a titanium alloy substrate (337.6 ± 14 HV) [15].…”

“…This makes it possible to obtain coatings with a lower elastic modulus compared to the implant material, which is closer to the characteristics of the bone. Moltasov et al (2022) analyzed the existing techniques for determining the modulus of elasticity of coatings and established their applicability and reliability [96]. The authors of the paper [96] have developed a new experimental-theoretical technique that allows determining the elasticity modulus of the coating in bending without separating it from the substrate: mathematical formulas have been obtained to determine the elasticity modulus of the coating in explicit form through the geometric dimensions of the coating and substrate and the modulus of elasticity of the substrate, and it has also been experimentally established that the flexural rigidity of the entire composition has a correlation not exceeding 5% between the calculated value of the elastic modulus and the experimental value.…”

“…Moltasov et al (2022) analyzed the existing techniques for determining the modulus of elasticity of coatings and established their applicability and reliability [96]. The authors of the paper [96] have developed a new experimental-theoretical technique that allows determining the elasticity modulus of the coating in bending without separating it from the substrate: mathematical formulas have been obtained to determine the elasticity modulus of the coating in explicit form through the geometric dimensions of the coating and substrate and the modulus of elasticity of the substrate, and it has also been experimentally established that the flexural rigidity of the entire composition has a correlation not exceeding 5% between the calculated value of the elastic modulus and the experimental value. In particular, a functional relationship has been established between the modulus of elasticity (Ec) of the microplasma-sprayed coating from zirconium alloy grade KTC-110 and substrate made of titanium grade VT1-00 and the porosity of coatings for cases when they are in the tensile zone (Ti − Ec = 22,460 − 397 P; Zr − Ec = 14,390 − 396 P) and in the compression zone (Ti − Ec = 57,680 − 1530 P; Zr − Ec = 37,730 − 1284 P), where P is the porosity of the coating, %.…”

Research of the structure and mechanical properties of microplasm porous coatings for biomedical purposes

“…It is known that the modulus of elasticity of coatings depends on the porosity of the material [2]. Thus, reducing the difference between the modulus of elasticity of the bone and the implant is possible with the application of a porous coating on the surface of the implant by the method of microplasma spraying (MPS) [3], as the modulus of elasticity of such coatings can decrease by more than an order of magnitude, compared to the original sprayed material, depending from the mode parameters of sputtering [4].…”