Microcutting of microcomponents made of steels which have to bear high loadings imposes severe problems concerning the tools and the materials states of the workpieces. Here normalized materials states, as commonly used in machining of macrocomponents, are not adequate because they need to be heat treated afterwards in order to adjust the properties necessary during service. Additionally, normalized materials states cause severe difficulties during microcutting due to fluctuations in the machining conditions caused by the change of ferritic and pearlitic regions. This means that microcutting of steels has to be performed with heat treatment states which have very fine and equidistantly distributed carbides achieved by quenching and subsequent tempering. As these states may be difficult to machine, it is expected that at intermediate tempering temperatures an optimum of machinability and service properties should be achieved. This paper deals with the determination of this optimum at the steels SAE 1045 (German grade Ck 45) and SAE 420 (German grade X42Cr13), in which grooves were micromachined by milling after different heat treatments.