Molecular dynamics (MD) simulation has been widely applied in various complex, dynamic processes at atomistic scale, because an MD simulation can provide some deformation details of materials in nano-processing and thus help to investigate the critical and important issues which cannot be fully revealed by experiments. Extensive research with the aid of MD simulation has provided insights for the development of nanotechnology. This paper reviews the fundamentals of nano-machining from the aspect of material structural effects, such as single crystalline, polycrystalline and amorphous materials. The classic MD simulations of nano-indentation and nano-cutting which have aimed to investigate the machining mechanism are discussed with respect to the effects of tool geometry, material properties and machining parameters. On nano-milling, the discussion focuses on the understanding of the grooving quality in relation to milling conditions.

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This paper aims to clarify the sphere forming mechanisms in vibration-assisted ball centreless grinding, a new technique for effectively processing balls using ultrasonic vibrations. Based on a comprehensive analysis of the ball rotation motion, geometrical arrangement and stiffness of the whole grinding system, a reliable mechanics model was successfully developed for predicting the sphere forming process. Relevant experiments conducted showed that the model had captured the mechanics and the major sphere forming mechanisms in ball centreless grinding. It was found that the ball whole surface can be well ground with a high accuracy, while efficiency is much enhanced compared with that in the traditional methods.The ball rotational speed which is controlled by the ultrasonic regulator has a great impact on final sphericity, and the speed controlled by the ultrasonic shoe dominates the whole processing time. To achieve a stable and high precision grinding, the ball needs to rotate rhythmically, and the wheel feed per step and the ball location angle should be controlled in a critical range.

This paper uses the molecular dynamics simulation to investigate the quality of nano-scale grooving on mono-crystalline copper by high-speed nano-milling and nano-cutting. The results reveal that nano-milling produces a high-quality nano-groove with smooth surfaces in comparison with a nano-cutting. It is also interesting to note that the machined workpiece subsurface can be free from dislocations.