Iron-filled CNT are a promising material for magnetic applications such as magnetic force microscopy (MFM) probes where a single Fe-CNT is attached to a conventional tapping mode cantilever tip. A continuous magnetic nanowire of several microns inside the CNT enables the use of an effective magnetic monopole model for a simplified quantitative data evaluation. Since the field of application demands certain properties of the filled CNT which are determined by the growth process it is crucial to control the synthesis conditions. It was found that one of the most important parameters to control the structure and morphology of the filling is the mass flow of the precursor. Furthermore, for applications such as scanning probes the mechanical properties are of great importance. In order to measure the mechanical properties of Fe-CNT single MWCNT were fixed to etched tungsten wires. This type of preparation resulted in samples that could be modeled as one side clamped free standing beams and dynamic resonant bending experiments were conducted. The elastic modulus has been determined using a continuum mechanics Euler Bernoulli beam model. The elastic modulus of multi-walled Fe-CNT was found in the range between 0.01 and 1.1 TPa. These values are comparable to the elastic modulus that were reported for unfilled MWCNT. The material has been successfully used for MFM probes and might be useful for other sensor and actuator applications in future.
Iron-filled CNT are a promising material for magnetic applications such as magnetic force microscopy (MFM) probes where a single Fe-CNT is attached to a conventional tapping mode cantilever tip. A continuous magnetic nanowire of several microns inside the CNT enables the use of an effective magnetic monopole model for a simplified quantitative data evaluation. Since the field of application demands certain properties of the filled CNT which are determined by the growth process it is crucial to control the synthesis conditions. It was found that one of the most important parameters to control the structure and morphology of the filling is the mass flow of the precursor. Furthermore, for applications such as scanning probes the mechanical properties are of great importance. In order to measure the mechanical properties of Fe-CNT single MWCNT were fixed to etched tungsten wires. This type of preparation resulted in samples that could be modeled as one side clamped free standing beams and dynamic resonant bending experiments were conducted. The elastic modulus has been determined using a continuum mechanics Euler Bernoulli beam model. The elastic modulus of multi-walled Fe-CNT was found in the range between 0.01 and 1.1 TPa. These values are comparable to the elastic modulus that were reported for unfilled MWCNT. The material has been successfully used for MFM probes and might be useful for other sensor and actuator applications in future.
