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In machine tools several time and position varying heat sources causes complex temperature distributions. The resulting problems are varying thermal deformations which cause a loss of accuracy as well as non optimal drive conditions. An option to deal with that issue is to use structure integrated SM-actuators which use the thermal energy accumulated by machining processes to yield an actuator displacement. That creates a structure inherent control loop. There the shape-memory-elements work as sensing element as well as actuation element. The plant is defined by the thermal and mechanical behaviour of the surrounding structure. Because of the closed loop operation mode, the mechanical design has to deal with questions of stability and parameter adjustment in a control sense. In contrast to common control arrangements this issues can only be influenced by designing the actuator and the structure. To investigate this approach a test bench has been designed. The heat is yielded by a clutch and directed through the structure to the shape memory element. The force and displacement of the actuator are therefore driven directly by process heat. This paper presents a broad mechanical design approach of the test bench as well as the design of the SMactuator. To investigate the thermo-mechanical behaviour of the structure-integrated actuator, a model of the test bench has been developed. The model covers the thermal behaviour of the test bench as well as the thermo-mechanical couplings of the shape memory actuator. The model has been validated by comprehensive measurements

An adaptive precision ball screw drive concept is presented in which a self-sufficient actuator is able to adjust the axial preload during the operation. The adjustment is effected by thermal shape memory alloy pucks, which either expand or contract according to the surrounding temperature field of the process. For this purpose, no external energy is needed and so the system is self-supported (energy harvesting). In this case, the extrinsic two-way shape memory effect occurs and the reversible full cycle of shape change is accomplished by a bias force of a flexure. Basing on temperature and force measurements on a double nut ball screw, a thermo-mechanical model is developed. Using the investigated principles adaptive mechanisms, a shape memory-based actuator is designed. Initial tests reveal an unwanted reduction of the preload of up to 800 N with rising temperature. Due to the shape memory actuation device, experiments results show an increase in axial load in approximated 70 % of the reduction

Microscale machining processes modifying component surfaces are applied in various fields: from drive technology through plant engineering to medical technology. The impact of the fine structures formed in the material on its behavior and mechanical properties need to be investigated in more detail. Besides the examination of the cyclic and quasi-static behavior of micromachined samples, analysing the near-surface microstructure and the hardness is of great importance. The nanoindentation allows for the determination of local mechanical properties in small analysis volumes. Its applicability to determine the hardness in micromachined near-surface areas including the metallographic preparation for commercially pure titanium is presented in this work.