Mechanical properties of metals can be largely degraded by the present of solute hydrogen, and this phenomenon is referred as hydrogen embrittlement. This phenomenon has been studied more than a century, however, its nature is still unclear. The main aim of this experiment is to analysis the strain evolution of the super duplex stainless steel with different dislocation density during tensile loading. Neutron diffraction spectrum can be collected and analysed to relate the width of the peak with the dislocation density. It is hoped that the outcome of this experiment will provide an insight into the hydrogen embrittlement in duplex stainless steel under in-service condition.