Manufacturing components for the nuclear industry requires large enclosed machining centres capable of accommodating the sheer size of the parts. Those machining centres are expensive to commission and they need a large infrastructure leading to the high costs associated with manufacturing. Robotic machining offers noticeable infrastructure savings. This could narrow down the infrastructure requirements leading to a general reduction of the high cost associated with new nuclear build.
Machining robots generally suffer from reduced static and dynamic stiffness when compared with machining centres. This renders them more prone to chatter type of vibrations. Especially at relatively low speed cutting of super-alloys, the low frequency modes of the robot may be excited at high amplitudes due to the high cutting forces at low excitation frequencies. In this paper, the effects of chattering, due to the dynamics of the machining robot, on surface integrity are evaluated comparing stable, mild and severe chattering conditions. Surface roughness and residual stresses are evaluated in robotic milling of alloy 690 using ceramic inserts. The results are discussed focusing on the effects of chatter vibrations due to the machining robot on the surface integrity.