The aim of this experiment is to measure the load transfer between g and g' in an advanced nickel¿base superalloy as a function of volume fraction of intragranular g' during in-situ loading at two different high temperatures. In a previous in-situ loading experiments on ENGIN-X we have demonstrated that we can observe a change in strengthening mechanism at high temperature when comparing fine and coarse g' microstructures We now want to change the volume fraction of intergranular and intragranular g' and study the effect on load transfer. This proposal is part of the Ni deformation programme proposal.