Reduction of vibrations during horizontal milling of aluminum parts : An Experimental and Numerical Study

Sammanfattning:

This thesis aims at vibration problem during milling operation. Vibration sets in at tool- workpiece interface if certain conditions are achieved. Research has been carried out try to reduce or eliminate chatter. Chatter decreases the dimensional accuracy and surface finish of workpiece.

Main objective is to examine the source of vibration and provide as solution to problem based on the findings. CAD Model of workpiece and clamping has been developed as close to real system as possible. Experimental modal analysis and Finite Element analysis is done to obtain system behaviour during vibration. Natural frequencies are determined and then compared with possible sources of excitation.

Modal testing and computer simulations are done before and after Final cutting operations to map out complete behaviour of system. Both forced excitation and self-excited vibrations are taken in consideration during measurements. Finally calculations are done to determine the solution and give recommendations. Suggestions for future work in this area are also provided that could enable SAAB to analyse and improve machining of all parts.