Optimization of the mechanical properties of machine tool with steel reinforced mineral concrete

Abstract

High damping and high static stiffness are essential to improve the static and dynamic characteristics of machine tools. Traditionally, the structural parts of machine tools are usually made of cast iron and steel, which may lead to poor surface finish and inaccurate dimensions of finished products. Therefore, many scholars have investigated other alternatives of structural material for machine tools, such as concrete, polymer concrete and epoxy granite. Although epoxy granite has better damping properties, its structural stiffness (as measured by Young’s modulus) is only 1/3 of the gray cast iron. Thus, this study would introduce several steel bar designs into epoxy granite to improve the static stiffness and quantitatively review the performance by finite element analysis. The results showed that the equivalent static stiffness and natural frequency were about 12 to 20% higher than the structural material of cast iron. Therefore, the proposed finite element model of vertical machining center (VMC) column in epoxy granite could serve as a feasible alternative to achieve higher damping or static stiffness, as it was also more environmentally friendly to the manufacturing process.