Predicting of Sn11Sb5.5Cu babbitt fracture using computer simulation at equal-channel angular extrusion

Abstract

The severe plastic deformation (SPD) methods are widely used to form ultrafine-grained structure in metals and alloys. They lead to a significant change in the physical and mechanical properties of materials. Since large deformations are accumulated during SPD the material loses its ability to deform and begins to break down. The purpose of this work was to predict the fracture of Sn11Sb5.5Cu babbitt with a different microstructure at equal-channel angular pressing (ECAP) based on the finite element modeling. The tin babbit (11 %Sb, 5.5 %Cu, Sn the rest, weight %), obtained by conventional casting with a different crystallization rate was chosen for study. The increase of crystallization rate led to the formation of a structure with smaller and uniformly distributed intermetallic particles. The equipment for ECAP consists of a matrix with vertical and horizontal channels crossed at angle 90° and a punch located in the vertical channel. ECAP was conducted at ambient temperature, a rod of square cross-section 9.7 × 9.7 mm and a length of 60.0 mm was deformed. The transfer speed of the punch was 1 mm / min. Computer modeling was performed using the DEFORM−2D software package. A model of the above described equipment and the sample was built. The comparison of computer simulation data and natural experiment was performed. It is shown that the metal damage calculated by the Cockroft-Latham method, installed in the DEFORM−2D, makes it possible to predict the failure of the babbitt Sn11Sb5.5Cu samples with different structures at ECAP.