Research on chip mechanism of Inconel 718 with ultrasonic assisted drilling by step drill

卷:126

Article

关键词: EXIT BURR;    DELAMINATION;    PERFORMANCE;    DESIGN;    MODEL;    TEMPERATURE;    ACCURACY;    ALUMINUM;    QUALITY;    TORQUE;   

DOI  :  10.1007/s00170-023-11212-8

来源: SCIE

【 摘 要 】

Nickel-based high-temperature alloys (Inconel 718) are considered to be difficult-to-machine materials with high yield strength and high-temperature strength properties and are widely used in the aerospace industry. Due to the low thermal conductivity of Inconel 718 material, it leads to severe machining hardening and easy to cause tool wear. In this paper, three step drills with different second point angles are proposed, the thrust force and torque models of twist and step drill bits are established, and then the critical burr generating states of the drills are analyzed. The experimental and finite element simulation analyses of the four drills showed that the thrust force, torque, burr, effective stress, and chip flow rate generated by the step drill under conventional drilling conditions were less than those of the twist drill. The torque and thrust force decrease as the angle of the second point angle of the step drill decreases. The smaller the second point angle of step drill, the higher the chip flow rate, the lower the maximum effective stress and the better the machining quality. In addition, the step drill is then compared with conventional drilling (CD) and ultrasonic-assisted drilling (UAD) to analyze the differences in temperature and chip morphology, and the results show that the machining temperature is lower and chip breaking performance is better under ultrasonic-assisted drilling.

【 授权许可】

Free