Optimum Design of the Precise Surface Plate Based on Thermal Deformation Experiment and FEA

Abstract

During the precision measurement and machining process, the temperature may change the shape and dimension of the machine parts. This kind of thermal deformation will lead to a decrease in the measurement accuracy and machining accuracy, and it will even affect the normal performance of the machinery. A precise flat plate is usually used as a benchmarking tool. Its flatness will be changed when the environmental temperature deviates from the standard temperature 20°C, which will influence the plate benchmark accuracy and result in erroneous measurement. The thermal deformation of conventional type and well-ribbed type precise flat plates were analyzed in this research. The finite element analysis software ANSYS simulation results indicated that their thermal deformation was not equal along the surface. The stress in the center was lower and showed a concentric circle distribution, while the stress at four corners was higher. So a ring-ribbed type precise flat plate was designed, and its ANSYS simulation and experimental results revealed that the ring-ribbed type flat plate had better anti-thermal deformation behavior, and its flatness was changed less with the temperature. Based on our research, it is suggested that the ring-ribbed type precise flat plate should take precedence in designing datum plane.

Keywords:

• Finite element analysis (FEA)
• Flatness
• Precise flat plate
• Temperature
• Thermal deformation

Acknowledgments

The investigation was supported by National Science Foundation of Anhui Educational Commission (No. 2012SQRL012), Ningbo Municipal Natural Science Foundation (No. 2011A610145), and Graduate Innovation Project of Anhui University.