Investigation on the cutting mechanism of SiCp/Al composites in ultrasonic elliptical vibration machining

Abstract

Aluminum (Al)-based silicon carbide (SiC) material composites are considered as difficult-to-machine materials because of the presence of hard reinforced SiC particles, which results in a greater cutting force and poor surface integrity during the machining process. This paper uses two finite element models to study the difference in the machining mechanism between ultrasonic elliptical vibration cutting (UEVC) and ordinary cutting (OC). Moreover, this paper mainly focuses on the influence of UEVC on cutting force, von Mises stress distribution, surface integrity, and chip formation. The models are validated by comparing chip shapes and machined surface features in OC machining Al/SiCp experience from the literature. Simulation results indicate that the cutting mechanism of Al/SiCp on UEVC is different from that of OC and has several good properties. At the same cutting parameters, high frequency vibration makes the cutting force of UEVC exhibit variable periodicity and reduces average cutting force. The instantaneous impact of tool and fast separation results in a more concentrated von Mises stress distribution, thereby resulting in the particles having a greater break degree than that obtained with OC. A comparison of the surface roughness values from the simulation result shows that UEVC obtains better surface integrity than OC does.

Research Status and Prospect of Ultrasonic Vibration and Minimum Quantity Lubrication Processing of Nickel-based Alloys

“…By introducing more than 20kHz vibration into the cutting process, the tool movement trajectory in the processing process is changed [12], so as to achieve the purpose of improving the processing efficiency and processing quality. At present, it is widely used in the processing of various difficult materials such as alloy materials, brittle materials and ceramic materials [13][14][15] UVAM can be divided into sine UVAM and elliptical UVAM according to the different characteristics of its tool trajectory, and can also be divided into turning UVAM and rotating UVAM according to the processing mode. Compared with traditional processing with non-ultrasonic vibration, the intermittent separation cutting characteristics produced by UVAM due to special tool trajectory is one of the most important advantages of UVAM, which can reduce cutting force and cutting temperature, extend tool life and improve the surface quality of the workpiece [16].…”