Equipment is described to analyze diffusion couples and phase boundaries by means of x‐ray absorption, in conjunction with the G.E. XRD diffractometers. Analysis may be carried out automatically with the system described here over a minimum distance of 14 &mgr;. The equipment will not interfere with normal diffraction work over the range 0–106°2&thgr; and, therefore, can be left fixed to the diffractometer when not in use.