Abstract
Experimental work was carried out using design of experiment to develop machining models for the dependent variables, tool life, cutting force and surface roughness, when machining a hardened AISI 420 martensitic stainless steel under oblique cutting. Carbide inserts were used as cutting tools in the present investigation. The effect of independent variables including cutting conditions, tool geometry, and hardness levels was investigated. The developed models were tested for the adequacy and validity of the present models. The correlation between dependent and independent variables is presented showing their relations. These models were utilized to find optimum cutting conditions using different optimization functions.