The recent interest in substitution of cobalt in cemented carbides has led to renewed efforts into finding alternative binders. Promising candidates are Fe and Ni-based systems which generally can be divided into austenitic (fcc) and martensitic (bct) binders. The martensitic transformation may drastically change the properties, thus, when designing an alternative binder it is important to know at what temperature and composition the martensitic transformation takes place. Furthermore, it is of interest to understand how the transformation is affected by the binder mean free path and the stresses in the binder introduced by the carbide grains. Another aspect, that is important for high temperature properties, is the temperature where the martensite starts to decompose, e.g. by precipitation of carbides and reversion to austenite. The effect of these parameters is here investigated along with how they influence the behavior of the cemented carbides at different temperatures, thereby determining their application range.