Papers by Author: Adam Bieńkowski

Abstract: The paper presents the possibility of using amorphous materials as cores of tensile stress sensors. Application of thermal annealing of the core to increase magnetoelastic sensitivity is presented. Important parts of measuring system are the signal processing circuit of the sensor and the sensor control system. The results of measurements of the characteristics of the sensors with signal processing circuit are presented.

Abstract: Paper discusses the possible of application of iron-based amorphous Fe₇₇Cr₂B₁₆Si₅ alloys for tensile force sensors. In proposed sensor uniform stresses were generated in direction of the ribbon ring core axis. As a result stresses were perpendicular to the magnetizing field direction, what increases sensor sensitivity as well as simplified analyses. The results show high magnetoelastic sensitivity of Fe₇₇Cr₂B₁₆Si₅ amorphous alloy. Moreover, this magnetoelastic sensitivity increases during the annealing process, which is connected with thermal relaxation of amorphous alloy.

Abstract: Paper presents a novel application of magnetostrictive delay lines, which give a possibility of real time monitoring of strain in ceramic components. Magnetostrictive delay line was based on highly magnetostrictive Fe-Si-B amorphous alloy ribbon, mounted outside of ceramic component, what is a new solution for increasing sensor’s sensitivity. Developed specially for this sensor, hybrid digital-analog signal processing unit covers the sample-and-hold integrated circuit. The achived sensitivity and repeatability of the sensor confirms, that such solution is suitable for ceramic machine tool monitoring.

Abstract: Paper presents the results of investigation on functional characteristics of magnetoelastic compressive force sensor utilizing two Fe81Si4B15 amorphous alloy ring-shaped cores. Uniform distribution of stresses in one of two cores was achieved owing to special non-magnetic backings. Signal from sensing coils of cores was connected to differential amplifier, whereas sine wave voltage signal was applied to magnetizing circuit. High stress sensitivity of developed sensor was indicated together with expected reduction of temperature sensitivity of magnetoelastic sensor. These results confirm, that differential configuration of magnetoelastic sensor is suitable for practical application in sensors development.

Abstract: The paper presents a new idea of extension of the Jiles-Atherton-Sablik model for modeling of the influence of mechanical stresses on magnetic hysteresis loops of amorphous alloys. In the extended model changes of parameter k are considered during the magnetization and the influence of stresses on eight parameters of the Jiles-Atherton-Sablik model is taken into account. Verification of the model was carried out on the base of experimental results obtained for Fe40Ni38Mo4B18 amorphous alloy subjected to both stress from external compressive force as well as shearing stresses from torque. In the experiment uniform stress distribution was achieved in both cases due to special mechanical system of backings. Evolutionary strategies were used in conjunction with gradient optimization for calculation of the model parameters. Results of simulation are in good agreement with experimental findings. As a result the extended Jiles- Atherton-Sablik model enables modeling of the magnetoelastic characteristics of amorphous materials for mechatronic inductive components such as compressive stress and torque sensors.