Temperature Measurements on ES Steel Sheets Subjected to Perforation by Hemispherical Projectiles Articles uri icon

publication date

  • July 2010

start page

  • 828

end page

  • 841

issue

  • 7

volume

  • 37

international standard serial number (ISSN)

  • 0734-743X

electronic international standard serial number (EISSN)

  • 1879-3509

abstract

  • In this paper is reported a study on the behaviour of ES mild steel sheets subjected to perforation by hemispherical projectiles. Experiments have been conducted using a pneumatic cannon within the
    range of impact velocities 5m/s<=V0<=60m/s. The experimental setup
    allowed evaluating initial velocity, failure mode and post-mortem
    deflection of the plates. The tests have been recorded using high speed
    infrared camera. It made possible to obtain temperature contours of the
    specimen during impact. Thus, special attention is focussed on the
    thermal softening of the material which is responsible for instabilities
    and failure. Assuming adiabatic conditions of deformation, the increase
    of temperature may be related to the plastic deformation. The critical
    strain leading to target-failure is evaluated coupling temperature
    measurements with numerical simulations and with analytical predictions
    obtained by means of the Rusinek-Klepaczko constitutive relation
    [Rusinek, A., Klepaczko, J.R. Shear testing of sheet steel at wide range
    of strain rates and a constitutive relation with strain rate and
    temperature dependence of the flow stress. Int J Plasticity. 2001; 17,
    87-115]. It has been estimated that the process of localization of
    plastic deformation which leads to target-failure involves local values
    close to for the boundary value problem approached. Subsequently, this
    failure strain level has been applied to simulate the perforation
    process and the numerical results obtained show satisfactory agreement
    with the experiments in terms of ballistic limit, temperature increase
    and failure mode of the target.