Papers by Keyword: Drilling Test

Abstract: This paper introduces the characteristics of sapphire and sapphire digging bits in LED field. The segment matrix design principle of bit and the rule of diamond selection are put forward. In addition, this paper analyzes the function of different metal powders and diamond parameters in the segment matrix. The results show that the finer grained (for example 80/100 mesh) diamond should be used with the concentrations of 30-60%. In the segment matrix, tin element can make the matrix more brittle and then the bit is sharper. Copper, silver and nickel element can enhance the matrix toughness and strength, cobalt and tungsten element can increase abrasive resistance. All of the above designs enable the sapphire bit to high sharpness and long life. A 4-inch sapphire bit was prepared for drilling sapphire crystal, the efficiency is increased by 8% than the Taiwan drill bit with the same specifications, the life is equal to Taiwan's drill bit, and the defect rate of sapphire bar is less than 0.5%, which satisfies the requirement of customers.

Abstract: The objective of this study is to compare the machinability of a sintered steel sample with that of a nodular graphite iron sample. We have developed a method that not only allows us to study the machinability, but also enables us to determine the optimum cutting conditions to suit criteria for maximum production or maximum quality. The method is based on a drilling test using constant axial force at the tip of the drill.