Experimental results of molybdenum specimens which were ion irradiated at several temperatures in the range of 700 to about 1500/sup 0/C at dpa levels of about 2 to 60 are discussed. TEM studies on Nb and Nb--1Zr irradiated at 1 x 10/sup 22/ n cm/sup -2/, E greater than 1 MeV at six temperatures in the range 430 to 1050/sup 0/C are presented. In addition, resistivity studies on W and W--25Re specimens irradiated under similar conditions as the Nb and Nb--1Zr specimens show significant changes coupled with void swelling in W but not in the W--25Re alloy. However, the W--25Re alloy showed that large precipitates have been formed thereby precluding the formation of voids. Finally, it has been shown that a hot-hardness tester may be effectively used as a strength microprobe in advanced alloy development and of irradiated metal and alloys where only small quantities of material are normally available. (auth)