The direct observation of point defects in irradiated or quenched metals by quantitative field ion microscopy

The progress made at Cornell University over the past few years in applying the field ion microscopy (FIM) technique to the study of point defects in irradiated or quenched metals is reviewed. The techniques involve essentially the atom by atom dissection of specimens by pulse field evaporation and the corresponding recording on film of the extensive number of FIM images produced at each stage of the process. The application of these techniques to the following problems are discussed: (i) the mobility of self interstitial atoms (SIA) in substage I_E of irradiated tungsten and platinum, (ii) the geometric configuration of the SIA, (iii) the point defect structure of depleted zones in tungsten and (iv) the properties of monovacancies and divacancies in quenched platinum.