Characteristics of Material Removal by Ceramic Media on Metallic Coupons for Mass Finishing Applications
Abstract
This dissertation introduces a fundamental concept of material removal by scratches made by ceramic media on metallic coupon as the basis for material removal by Mass Finishing process. Mass Finishing is a group of surface improvement operations such as polishing, descaling, burnishing, cleaning, and drying. Polishing, descaling, and burnishing are abrasive operations that remove or displace material on parts being processed to attain the expected effect. These material removal operations were idealized as a sequence of scratches. A series of experiments for generating scratches were conducted using an abrasive sphere on a flat polished surface of three distinct materials. The abrasive tool is a spherical ceramic piece with a surface roughness of 3.7μm and a diameter of 14.288mm, and the materials for the scratch test are steel, brass, and aluminum, with their surfaces polished to a finish better than 0.1μm. Physical properties of these materials such as yield strength, strain hardening coefficient, and strength coefficient were measured. Empirical relationships for the width and depth of the scratch with respect to process and material characteristics were developed using dimensional analysis. The theoretical output from these relationships showed a close match with the physical data obtained from experiments. This indicated that the dimensional analysis technique is a viable tool for use in this aspect of Mass Finishing research.