Investigation of the properties of ion-implanted shape memory titanium alloy used in the construction of mining equipment

Abstract

Introduction. Currently, nickel-titanium alloy has a noticeable spread in the mechanical engineering and mining industry. Modification of the properties of this alloy by ion-implantation is also being developed. Methods and materials of research. For research, experimental samples of Ti-Ni alloy in coarse-grained and finegrained structural state were specially manufactured before and after implantation with various ion beams with a dose of D = 2.3 × 1017 ion/cm2 with an energy of 40 keV. All samples were examined using: nanoindentation, microhardness measurements and X-ray diffraction analysis. Research results. The results of nanoindentation showed that the Ti-Ni alloy samples in the coarse-grained and finegrained state after ion-implantation had a higher hardness compared to the initial state. The increase in hardness in all samples is associated with the formation of a large number of radiation effects. The modulus of elasticity for the finegrained state practically does not change after ion bombardment. Discussion of research results. The microhardness study was carried out to determine the depth of the hardened layer after ion-implantation for samples in coarse-grained and fine-grained states. The greatest microhardness was detected at the sample surface in the nanostate (fine-grained) after irradiation with titanium ions. X-ray diffraction analysis of TiNi alloy samples in the nanostructured state before and after implantation with nickel and titanium ions with a dose of D = 2.3 × 1017 ion/cm2 at low-angle intensity peaks was carried out. It showed that ion-implantation leads either to a decrease in the amount of the monoclinic structure of the material, or to a significant decrease in it. Conclusion. Investigation of the process of ion-implantation of titanium-nickel alloy in coarse-grained and fine-grained state by titanium and nickel ions has shown that exposure leads to: - an increase in the hardness of the material by 20% and 6%, respectively; - a decrease and no change in the modulus of elasticity, respectively; - increase of microhardness by 100% and 40%, respectively; - not noticeable and noticeable change in the structure of the surface layer, respectively. Conclusions on the article. The obtained research results show that ion-implantation of titanium-nickel makes it possible to further increase the reliability of loaded mining equipment units, increase its service life and reduce the wear of critical parts. Suggestions for practical application and directions for future research. The results shown allow us to propose a method of ion implantation as a hardening treatment of particularly critical parts used, in particular, in the mining industry. In order to develop ion implantation as one of the strengthening technologies, it would be advisable to continue the study of various physico-chemical properties after exposure to ion implantation.