Machine tool structures produced with Epoxy Granite reinforced polymer composites (EGPCs) have gained prominence in recent years and have replaced conventional cast iron materials and other metals due to its remarkable damping characteristics. However, machine tool structures manufactured with EGPCs tends to exhibit limited strength, stiffness and stability. Such challenges in EGPCs are resolved by incorporation of steel as additional reinforcement and enhanced mechanical properties are observed in these hybrid machine‐tool structures. Hybrid epoxy granite machine tool structures with enhanced mechanical performance are prone to thermal errors resulting in machining inaccuracies and limited performance. Thermal errors induced in machine tool structures could be attributed due to effect of temperature distribution and displacements at the Tool Center Point (TCP). This review work carried out focuses predominantly on design methods adopted in resolving the challenges identified in development of machine tool structures and further analyses results of several polymer concrete‐based machine tool structures with regard to static, dynamic and thermal characteristics. Several review works conducted earlier have discussed the results of static and dynamic characteristics, whereas this review work provides additional information on thermal based errors induced and discusses the methods adopted in compensation of thermal errors. In this review paper, research studies pertaining to static and dynamic characteristics of different machine tool structures performed in last three decades have been discussed and a wholistic information is provided in relation with static, dynamic and thermal characteristics and properties toward developing a machine tool structure with a novel, newer class or alternative materials.

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Polymer concrete or epoxy granite is now becoming more popular for beds, bases, and other structures of precision machine tools, owing to its excellent damping characteristics. In order to realize the same static rigidity as that of the cast-iron structures, steel-reinforced epoxy granite (SREG) structures are being used. The vast differences in the thermal properties of steel and epoxy granite (EG) are likely to cause higher magnitudes of thermal error. The objective of this work is to investigate the thermal behavior of a CNC lathe built with an SREG bed and compare its performance with the lathe with cast iron bed. Experimental and numerical investigations have been carried out under cross feed drive (CF) idle running conditions to determine the TCP deformation. The results reveal that the thermal error in the CNC lathe with SREG bed is 1.68 times that of the lathe with CI bed at 20ºC and 1.8 times at 40ºC environmental temperature variation chamber (ETVC) conditions. It could be identified that the heat generated in the CF is conducted to the steel guideways embedded in the SREG bed, but further heat transfer to the EG portion of the bed is impeded and hence the heat accumulation that occurs in the guideways leads to higher magnitude of thermal error. The experimentally validated numerical model is used to extend the investigations to study the effect of the idle running of the longitudinal feed drive (LF), and combined cross and longitudinal feed drives, on the thermal behavior of the lathe.

Polymer concrete or epoxy granite is becoming more popular for beds, bases, and other structures of precision machine tools, owing to its excellent damping characteristics. To realize the same static rigidity as that of the cast-iron structures, steel-reinforced epoxy granite (SREG) structures are being used. The vast differences in the thermal properties of steel and epoxy granite (EG) are likely to cause higher magnitudes of thermal error. This work aims to investigate the thermal behaviour of a computerized numerical control (CNC) lathe built with a novel dynamically enhanced SREG bed and compare its performance with the lathe with a cast iron bed. Experimental and numerical investigations have been carried out under cross-feed (CF) drive idle running conditions to determine the TCP deformation. The results reveal that the thermal error in the CNC lathe with SREG bed is 1.68 times that of the lathe with cast iron (CI) bed at 20 ºC and 1.8 times at 40 ºC environmental temperature variation chamber (ETVC) conditions. It could be identified that the heat generated in the CF is conducted to the steel guideways embedded in the SREG bed, but further heat transfer to the EG portion of the bed is impeded, and hence the heat accumulation that occurs in the guideways leads to higher magnitude of the thermal error. The experimentally validated numerical model is used to extend the investigations to study the effect of the idle running of the longitudinal feed drive (LF) and combined cross and longitudinal feed drives, on the thermal behaviour of the lathe.