Abstract: A harden screw form and methods of making same for use with, for example, positive displacement rotary axial screw pumps are disclosed. The methods include the use of a CNC machine with a laser and a special, newly developed optic for selectively hardening the contact areas of screw forms, such as for example, rotors used in positive displacement rotary axial screw pumps such that the rotor undergoes only controllable or predictable distortion as a result of the hardening process. Hardened screw forms manufactured by the CNC/laser/optic process that are free of uncontrollable or unpredictable distortion are also disclosed.