The current approach to developing structural materials for fusion reactors requires a heavy reliance on the use of small irradiation specimens largely because of limitations in available irradiation volumes. The miniature Charpy-V-notch specimen (MCVN) is one of several techniques currently under development. It has particular potential application in addressing problems associated with fracture mode transition in ferritic/martensitic steels. The authors have previously reported a technique for testing MCVNs that are one-third the size in all dimensions of a standard Charpy-V-notch (CVN) specimen. This involves an instrumented drop tower and a computerized data acquisition/processing system. We have now tested a variety of ferritic steels using MCVN specimens and compared the data to CVN data obtained by ourselves or others. These materials include A302B correlation monitor material, A508 forgings, Ht-9, a high-copper A533B weld, and an A710 copper-bearing steel heat-treated to four conditions. These heat treatments result in age hardening by copper precipitation and correspond to underaged, peak-hardened, and overaged conditions. The MCVN test appears to provide data that are both qualitatively and quantitatively similar to CVN data. The most promising approach to applying MCVN tests, in our opinion, is to extract fundamental property data. Even so, there are a number ofmore » differences between MCVN and CVN tests that remain to be sorted out.« less