  A series of irradiation tests have been performed at TRIUMF to investigate
different material pairings to act as high-power electron-to-gamma converter
for the ARIEL Electron Target East (AETE). The bulk of the converter body will
be made out of an aluminum alloy with a sub-millimeter high-Z metal layer
bonded to the surface facing the incoming electron beam. This contribution
presents the approach chosen to select the optimal material for the high-Z
layer, describes the tests performed and shows result which led to the
successful selection of a specific tantalum-aluminum pairing as the future
ARIEL converter material.
