The ultrasonic wave interaction with porosity defects in welded rail head

Abstract

There are several millions aluminothermic welds and thousands of new welds being made daily on the European rail network. Although the aluminothermic welding technique is well proven, it is a critical safety component of the rail infrastructure. The consequences of a single failure could result in the derailment.
The objective of this investigation was to verify the influence of the depth of the porosity type defect on strength of the reflected ultrasonic signal when the ultrasonic phased array is at the fixed position. The propagation of the ultrasonic wave in the rail head with porosity type defects has been modelled using ANSYS finite element code and CIVA software.
The presented results demonstrate the influence of the depth of the porosity defect for 35 mm weld, when the defect is located in the middle of the weld.