By diffusion bonding, internal cross sections are joined, forming monolithic parts with superior pressure resistance. The main process parameters are bonding temperature (T), dwell time (t), and contact pressure (p). The drawback is, that, if constant parameters are used, the resulting deformation is difficult to predict and depends strongly on the geometry and aspect ratio of the parts to be bonded. Furthermore, the deformation required to obtain high vacuum tight parts, varies depending on the number of layers to be joined and the surface roughness, since all surface asperities must be levelled to make intimate contact on microscopic scale and to enable diffusion of atoms across individual layers. The approach presented here by applying a peak contact pressure and low contact pressure afterwards was approved at different sample geometries. Finally, an industrial part consisting of more than 1000 layers and completely different design boundaries was successfully bonded.