Comparative erosion tests results of titanium alloy Ti-6Al-4V samples obtained by using 3D - printing technology and manufactured by the traditional technological method

摘要

Rotating blades of steam turbines and compressors operate in conditions of various damaging factors, including shock-dynamic impacts of liquid droplets contained in steam or in air. One of the most promising ways to reduce damage from water droplet erosion can be the application of the 3D - printing technology that will allow to replace damaged parts of structural elements, as well as cut repair costs and prolonging the service life of the equipment. The aim of present work was to determine the possibility of using the 3D - printing technology of the turbine blades for use in power engineering. The main task of the work was to check samples of the material obtained by this method for water droplet erosion resistance, which is one of the regulated tests type at the turbine blades design stage. This paper presented the results of water droplet erosion process experimental studies of the titanium alloy Ti-6Al-4V samples prepared by the method 3D - printing and by the traditional technological process at a collision velocity Cimp = 300 m/s with a monodisperse flow of liquid droplets with a diameter dd = 1000 μm. Erosion tests were carried out by using a set of research equipment URI 《Hydroshock rig 《Erosion-M》 NRU 《MPEI》. It has been established that the erosion resistance for the incubation period duration of the Ti-6Al-4V titanium alloy samples manufactured by the 3D - printing method is 1.4 times less than for the samples manufactured by the traditional technological process. The data obtained can be used in the future in the development of complex passive methods for protection steam turbines and compressors last stages rotating blades: creation of replaceable erosion-resistant inserts by 3D - printing with a protective coating.