Complexity of MNT
Pp. 221-270 (50)
The physical process involved in the MNT is unique which makes it a special
area of machining science. The reason for this is that the minimizing of the workpiece
or machining precision level is greatly improved in the MNT comparing with the
traditional machining technique. Mechanical properties of materials are scale dependent
based on the strain gradient plasticity and the effect of dislocation-assisted sliding.
When material is removed by machining, there is a substantial increase in the specific
energy required with decrease in chip size. It is generally believed that this is because
all metals contain defects (grain boundaries, missing and impure atoms, etc.), and, when
the size of the material removed decreases, the probability of encountering a stressreducing
defect decreases. Furthermore, the dominate role of the volume force in the
larger scale is replaced by the surface force such as adhesive force at this micro & nanolength
scale. The generation and dissipation of heat and the materials plastic
deformation also involved different control mechanism from the macroscopic scale.
Traditional metal cutting principle cannot give a reasonable explanation about
phenomenon in the MNT. MNT is a novel challenge that should be studied in depth
using ideas of modern physics that deals with the problems of complexity. This chapter
devoted to the introduction of studying MNT using complexity theory (selforganization,
nonequilibrium thermodynamics, fractal theory etc.) and some new
Complexity, dynamic evolution, self organization, dynamic
equilibrium, energy dissipative mechanism.
School of Mechanical Engineering Tianjin University P.R.China