  Resin-impregnated high-field Nb3Sn type of accelerator magnets are known to
require extensive training campaigns and even may exhibit performance-limiting
defects after thermal or electromagnetic cycling. In order to efficiently
explore technological solutions for this behaviour and assess a wide variety of
impregnation material combinations and surface treatments, the BOnding
eXperiment (BOX) sample was developed. BOX provides a short-sample test
platform featuring magnet-relevant Lorentz forces and exhibits associated
training. Here we report on the comparative behaviour of BOX samples comprising
the same Nb3Sn Rutherford cable but impregnated either with common resins used
in high-field magnets, or with less conventional paraffin wax. Remarkably, the
two paraffin wax-impregnated BOX samples reached their critical current without
training and are also resilient to thermal and mechanical cycling. These rather
encouraging results strongly contrast to those obtained with resin impregnated
samples, which show the characteristic extensive training and at best barely
reach their critical current value.
