Konferenzbeiträge

The paper presents some of the results of the static and dynamic force measurements at 100 nN to sub-10 [my]N ranges which are generated due the photon-momentum. The force sensor with resolution about 20 nN and operating in differential measurement mode is developed by two electromagnetic force compensation balances. In order to generate these calibration forces, CW lasers with different operational modes, power levels, and wavelengths are used. Multi-reflection configuration of the laser beam inside the macroscopic cavity with highly reflective mirrors are used to test and variate the total amount of the forces.

The Planck-Balance is a table-top version of a Kibble balance. In contrast to many other Kibble balances, the coil is moved sinusoidally and an ac rather than a dc signal is generated in the velocity mode. The three-parameter sine fitting algorithm is applied to estimate the amplitudes of the induced voltage and the coil motion, which are used to determine the force factor Bl of the voice coil of the electromagnetic force compensation balance. However, the three-parameter sine fitting algorithm is not robust against some perturbations, e.g. additive Gaussian white noise, quantization error, harmonic distortion, frequency error and time jitter. These effects have influences on the accuracy of the amplitude estimation. Based on numerical simulations and correlation analyses, the effects of these perturbations are determined. By optimizing measurement and data processing approach, the bias and standard deviation of the estimated amplitude can be effectively reduced, and thus the accuracy of the force factor Bl in the velocity mode can be improved.

The Planck-Balance 1 (PB1) has been developed in a collaboration between the Physikalisch- Technische Bundesanstalt and the Technische Universität Ilmenau. It is a small-size Kibble balance aimed to calibrate E1 mass standards for a mass range from 1 mg to 1 kg. This paper presents its principle and some preliminary investigations.

Components made of aluminum-steel dissimilar joints show a high potential regarding to lightweight applications. In particular, due to their fundamental differences in chemical and physical properties, new approaches must be developed for common industrial joining processes. This study shows a new approach in order to characterize the joining zone formation using single-sided resistance welding. Based on the mechanical properties, the interface formation is investigated. Depending on the process variables, increasing mechanical tensile forces are shown with simultaneously increasing thickness of the diffusion zone. In this context, a significant porosity of the joint in the aluminum base material can be observed. For this purpose, a characterization method is developed.