The dynamic material model (DMM) method has been widely used for the macroscopic description of flow, fracture, and workability of materials under hot deformation. This investigation is aimed at proposing a new methodology for the optimization of hot machinability of a material using the DMM stability criteria. The constitutive flow behavior of Al-20 pct SiC has been evaluated in the temperature range 50°C to 350°C and the cutting velocity in the range from 25 and 300 m/min with the view to optimizing its machinability using the DMM instability parameters. The DMM instability parameters predicted a narrow region around 150°C and 150 m/min as the optimum domain for machining this material. It has been observed that the tool wear is minimum at optimal conditions. This investigation proved that the machinability could be optimized through the DMM.