Search academic texts

Information × Registration Number 0222U000717, 0120U101737 , R & D reports Title Development of technology for surface modification of titanium components of friction pairs of artificial joints popup.stage_title Head Pohreliuk Iryna M., Доктор технічних наук Registration Date 18-01-2022 Organization Karpenko Physico-Mechanical Institute of NASU popup.description2  The technology bases of modifying the surface of the titanium component of the friction pair of the artificial joint by combining cold surface plastic deformation (CSPD) and thermodiffusion nitriding (TDA) has been developed. Based on kinetic studies of low-temperature nitriding in nitrogen atmosphere and its rarefied dynamic flow in the temperature range 650…750°С, correlations between saturation parameters, level of near-surface hardening and phase-structural state of modified surface layers of technically pure titanium B are obtained. The parameters of chemical-thermal treatment of technically pure titanium VT1-0 are recommended to obtain regulated near-surface hardening (nitride zone thickness 0.5…2.0 μm, depth of diffusion layer Ti(N) ³ 50 μm, surface roughness Ra ≤ 1.25 μm surface microhardness Нп0,49 ³ 6 GPa). It was found that the nitride coating formed under the optimal nitriding regime improves the anticorrosion protection of technically pure titanium VT1-0 in the physiological environment by 2 times. It is shown that the number of living pseudo normal cells in the presence of titanium decreases, and in the presence of nitride coating - remains. It is established that the previous HPPD significantly affects the formation and characteristics of the gradient diffusion layer in TDA technically pure titanium VT1-0. It is shown that the microhardness of the near-surface layer 20 μm thick, formed after the combined treatment, is 1.3–1.4 times higher than after nitriding. Increasing the degree of deformation hardening helps to increase the microhardness of the nitrided layer. It is established that a larger gradient of microhardness of the strengthened nitrided near-surface layer is formed during rolling in liquid nitrogen than during rolling in air. It is established that thermodiffusion nitrogen saturation of technically pure titanium BT1-0 increases its efficiency by 1-2 orders of magnitude in combination with ultra-high molecular weight polyethylene (UHMWPE) Product Description popup.authors Kordyukevych Myron O. Krayevsʹkyy Petro P Kravchyshyn Taras M. Lavrysʹ Serhiy M Lukʺyanenko Oleksandr He. Petryshyn Mykhaylo Stefanovych Pohreliuk Iryna M. Tkachuk Оleg V. Trush Vasylʹ S Fedirko Viktor M popup.nrat_date 2022-03-09 Close