Papers by Keyword: Diamond Coated Tool

Abstract: The high speed milling of silicon carbide was discussed by using flat end-mill 2 mm in diameter diamond coated tool. Ultra-precision high speed spindle attachment was used to achieve cutting tool rotation speed as high as 50,000 rpm. Special fixture was designed to minimize the chatter on work-piece surface during the machining process. Three cutting parameters were selected as independent variables of the experiments. They were spindle speed, depth of cut and feed rate. The arithmetic mean value of roughness (Ra) was measured on the work-piece surface as the response of the experiment. Result of the experiment shows that the value of surface roughness can be achieved as low as 0.150 μm. Statistical analysis was provided to study the significant of the model, interaction among the cutting parameters and their effects to the surface roughness value.

Abstract: This paper presents the thorough experimental analysis on high speed end milling of single crystal silicon using diamond coated tools. Experiments were conducted on CNC milling machine. The design of the experiments was based on the central composite design (CCD) technique of Design Expert software. Response Surface Methodology (RSM) was used to develop mathematical imperial model to establish a correlation between machining parameters (cutting speed, feed and depth of cut) and machined surface roughness in high speed end milling of single crystal silicon using 2mm diameter diamond coated tools. The optimum machining parameters were determined using the optimization tool of Design Expert software based on the desirability function. Finally, confirmation tests were performed to validate the developed model.

Abstract: CVD diamond coated inserts with different coating thickness are fabricated using hot filament chemical vapor deposition (HFCVD) method. Scanning electron microscope (SEM) and Raman spectroscopy are introduced to characterize the diamond films. The cutting performance of as-fabricated CVD diamond coated inserts is evaluated in dry turning aluminum alloy. The uncoated WC-Co tool is also adopted in the cutting tests for the sake of comparability. The testing results show that diamond coated tools exhibit much better cutting performance. Coating thickness affects the characteristics of diamond coated cutting tools, the thicker of coating, the more adhesive chips, but the better delamination resistant. The uncoated WC-Co tool suffers adhesive wear for the built-up edge (BUE) breaking.

Abstract: CVD diamond films are deposited on cobalt cemented tungsten carbide (WC-Co) endmills using hot filament chemical vapor deposition (HFCVD) method. Scanning electron microscope (SEM) and Raman spectroscopy are used to characterize the as-deposited diamond films. To evaluate the cutting performances of as-fabricated CVD diamond coated endmills, dry milling tests are conducted using aluminum alloy as the workpiece material. The uncoated WC-Co endmills are also adopted in the milling tests for the sake of comparability. The experimental results show that the build-up edge formed on the uncoated WC-Co endmills at very early stage of the cutting tests. Comparatively, CVD diamond coated endmills present an excellent anti-adhering property. The result suggests that depositing diamond coating on WC-Co endmills is a viable way to improve their cutting performances in machining of aluminum alloy materials