Computer Controlled Ultra-precision Polishing (CCUP) provides an enabling technology for machining freeform components with optical surface quality (i.e., nanometer surface roughness and sub-micrometer or accuracy). It can be used to machine difficult-to-machine materials such as optical glass which are not amenable for diamond machining. Due to the complexity of material removal mechanism in t...

In the moulds and dies manufacturing it is important to reduce the manual polishing time after end milling processes. The polishing difficulty is related to surface topography shape and roughness values obtained in the previous end milling processes. It is interesting to develop a methodology and a test to evaluate the polishing difficulty. The aim of the present work is to establish a methodol...

Axiomatic Design was used to develop a complete platform for chemical mechanical polishing (CMP) of silicon wafers. A functional requirement of the machine emerging from the axiomatic design process is the control of the wafer-scale polishing uniformity. Mechanisms to maintain control of the uniformity were designed, and integrated into a wafer carrier, which holds the wafer during polishing an...

Demands are increasing for micro axis-symmetric aspherical lenses to be installed in various optical devices. The micro glass lenses are generally molded by glass press process with micro aspheric ceramic molding dies or molds made of tungsten carbide or silicon carbide. These dies and molds are mostly ground with micro diamond wheels, but require additional finishing process as the size of the...

The centrifugal shooting type polishing machine is a recently developed apparatus that seeks to improve the efficiency and environment of polishing removable prostheses. In an attempt to optimize the effectiveness of this apparatus, this study examined the influence of the shooting angle of polishing particle on the surface roughness of cobalt-chromium alloy casting specimens. Polishing was per...

This study evaluated the influence of the manipulation technique and polishing method on the flexural strength and cytotoxicity of acrylic resins. Two manipulation techniques and three polishing methods were used in the fabrication of acrylic plates that were divided into 6 groups (n=10). Groups MM, MC and MW: mass technique with mechanical polishing, chemical polishing and without polishing, r...

This paper reports ductile or partial ductile mode machining of silicon, glass and some advanced ceramics. Results are presented using scanning electron micrographs of the machined surfaces. Grinding and lapping operations using inexpensive machine tools could produce ductile streaks on surfaces of these brittle materials under good conditions. Manufacture of spherical glass lenses by the fract...

Cavities and ageing leads to a higher demand for robust and durable dentures. Cobalt chromium dental cast alloys fulfill these requirements. After the casting, the alloys have to be thoroughly cleaned in an electrochemical dissolution bath. In the existing technology an expert has to control the polishing process. In this paper we present a fuzzy logic controller with 16 fuzzy rules, which comp...

We present an overview of the engineering design and empirical performance of four stressed-lap polishing tools developed at the University of Arizona. Descriptions of the electromechanical actuators, servo systems, computer interfacing, and attachment of the lap to the polishing machine are provided. The empirical performance of a representative tool is discussed in terms of accuracy, repeatab...