Assessment of Non-Linear Dynamics of Material Removal on Surface Integrity
  
Guangming Zhang, Stanley J. Ng, and Dung T. Le Department of Mechanical Engineering & the Institute for Systems Research University of Maryland College Park, Maryland 20742
 

 

1. INTRODUCTION 

 
Advanced ceramics offer many desirable characteristics for industrial and commercial use in terms of their high temperature tolerance, wear and abrasive resistance, and corrosion resistance. These intrinsic properties have led ceramics to be prime candidates for many applications ranging from engineering components to dental restorations. However, the machining of ceramics into practical forms presents a challenge because of the non-linear dynamics involved in the material removal process inherent by its high hardness and high brittleness.

Manufacturing of ceramic parts requires dimensional and geometrical accuracy. Machining has played a key role in this respect to ensure the functionality of surfaces of ceramic parts, especially after sintering. However, due to their hard and brittle nature, ceramic materials are difficult to machine. The fracture-dominated material removal process in ceramics machining leaves cracks on and beneath the machined surfaces, forming surface and subsurface damage and leading to a shortened product life cycle. Moreover, the high wear rate of cutting tools or grinding wheels during machining gives rise to high production cost. The non-linear dynamics can be best described by the basic five stages of the material removal mechanism in advanced ceramic material, as illustrated in Figure 1.

 
 

 
Figure 1. Five Essential Stages of the Material Removal Mechanism in Ceramics