Effect Produced by the Treatment Type on the Performance of the Artificial Heart Valve Welded Frame

Abstract

Background: The welded joint loss of performance is largely determined by the heterogeneity of the structural state of the heat-affected zones. The basic materials from which the artificial heart valve welded frames are made are technically pure titanium grade VT1-OS and alloy grade 40 KHNM with the required biomedical properties. Objective: The study of the structural state, and changes in mechanical characteristics under static and cyclic loading of welded joints made of pure titanium grade VT1-OS and alloy grade 40 KHNM. Method: The paper investigates structural changes and mechanical characteristics under static and cyclic loading in Ringer-Locke saline solution of welded T-shaped joints made of pure titanium grade VT1-OS and alloy grade 40 KHNM, simulating the nodes of an artificial heart valve subject to maximum cyclic loads during operation. Result: It is revealed that the structural and mechanical heterogeneity along the length of the welded joints of the studied materials determines a loss of mechanical performance, both under static and cyclic loading. Conclusion: Experimental batches of welded elements of artificial heart valve assemblies made of VT1-OS titanium and 40 KHNM alloy according to the established optimal modes have successfully passed full-scale tests on physiological and biological stands in conditions as close as possible to the operational ones.