OBTAINING FIXED JOINTS USING ULTRASONIC VIBRATIONS

Obtaining fixed joints is one of the most demanding and time-consuming stages of assembling machine-building products. The quality of all-in-one connections determines the reliability of the machine as a whole. This determines the relevance of research aimed at improving the quality of non-removable compounds and at the intensification of their production processes. An effective way to solve this issue is the use of ultrasonic vibrations. The imposition of vibrations on the welded elements leads to a change in the crystallization parameters, grinds the microstructure of the weld, reduces welding deformations and increases the strength of the joint. Deformation of the rivet with an ultrasonic tool takes place when the required force is reduced by more than 10 times and ensures uniform distribution of radial stresses, making shear strength better this way. Ultrasonic treatment of the binding material within the process of its production and oscillation superposition on the adherend parts reduce the viscosity of the adhesive, increase wettability and filling capacity, resulting in shear strength hardening in the adhesive joint. The transmittal of ultrasonic vibrations of the pressed part decreases friction due to its transformation into a quasi-viscous one, which takes down the required pressing force and reduces damage probability for mating surfaces. Ultrasonic cavity-abrasive treatment of complex metal products obtained by additive manufacturing methods makes it possible to reduce roughness in hard-to-reach areas and surface elements, which is not possible by other methods. For each fixed joint type under examination, technical plans are proposed, including both standard operations and additional ones using ultrasonic vibrations, which makes properties improvement for the obtained fixed joints possible.

ultrasound, vibrations, fixed joints