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Micro-Drilling of Pre-Sintered Alumina Ceramic

Ceramic materials are widely used in industries because of their excellent properties such as high hardness, strength, resistance to heat and corrosion. The high strength of sintered ceramics posts the difficulty to be processed into the desired shapes and dimensions. Direct processing of ceramic green body is easy to cause edge damage due to the lower strength, leading to low surface accuracy. When the green body of ceramics is pre-sintered, the mechanical strength of green body is enhanced and the machining accuracy is improved. In this paper, micro holes are drilled in ceramics sheets pre-sintered at different temperatures. The influence of processing parameters is analyzed. It was found that the tool has the longest life when the pre-sintering temperature of ceramic green body was 800°C. The quality of the inlet and outlet of micro holes was improved significantly when the coolant was used in machining.