The amount of energy per unit volume to remove material from the workpiece during a machining operation, measured in horsepower per cubic inches per minute. The specific cutting energy, also known as unit power, is a material property but is also affected by the type of machining operation and the material and sharpness of the cutting tool. Values for specific cutting energy are typically in the range of 0.1 -2.5 hp/in^3/min (most steels have a value of 1.0-1.5 hp/in^3/min).