Molecular dynamics study of tensile behaviour for cold and linear friction welded single crystal tungsten

Abstract

In the present paper, single crystal tungsten model has been established by using molecular dynamics simulation. The joining of two single-crystal tungsten has been shown using two different welding techniques namely Cold welding and Linear Friction Welding (LFW) at room temperature. The tungsten atom interactions have been developed using the Embedded Atom Method potential. The Radial Distribution Function (RDF) simulation has been performed for two different layer thickness around the welded region for structural analysis. It has been found that as the layer thickness increases the probability of getting perfect structure atoms in long range order decreases. It has also been observed that few dislocations are generated during welding. The tensile properties have also been investigated for the sample joined by two processes for 50 ps, 100 ps and 150 ps at a strain rate of 1.5 × 109 sec−1. The results show that the joint developed by cold welding process at 100 ps resulted in a yield strength of 3588 MPa and ultimate strength of 6678 MPa. During LFW yield strength (5152 MPa) and ultimate strength (7172 MPa) is achieved in less welding time i.e. 50 ps.