Flatness Change of Vacuum Chuck for Ultra-precision Machining Due to Thermal Deformation (1st Report)

Thermal Behavior of Vacuum Chuck

Abstract

This paper deals with experimental analysis of thermal behavior of vacuum chuck for a basic investigation to design a chuck with very little flatness change due to thermal deformation. It is clarified that the temperature rise of chuck is nearly the same as that of spindle. And the free thermal expansion of aluminum alloy chuck in radius is larger than that of steel spindle. But chuck and spindle are bolted together, and then radial thermal displacement of chuck is constrained. The sliding distance between chuck and spindle and the ratio of sliding distance to difference between radial free thermal expansions of chuck and spindle are strongly influenced by bolt thrust and chuck thickness, not by bolt material.