Fast, Preisach-like characterization of hysteretic systems

Proposed is a substantially simplified, Preisach-like model for characterization of hysteretic systems, in particular magnetic systems. The main idea is to replace a two-dimensional Preisach density with just two real functions, describing in a {\em unique way} the reversible and irreversible processes. As a byproduct of our model we prove, that the major hysteresis loop alone is insufficient to produce the unique Preisach map. Keywords: magnetic hysteresis; magnetization processes; materials testing; modeling.Comment: 7 double spaced pages, 4 figures. Presented at 5th International Symposium on Hysteresis and Micromagnetic Modeling, Budapest, Hungary, May 30th - June 1st, 200

Magnetic nondestructive testing and the Preisach model formalism.

Available from STL Prague, CZ / NTK - National Technical LibrarySIGLECZCzech Republi

ON THE ISSUE OF TRAFFIC SAFETY TRANSPORT AND TECHNOLOGICAL SYSTEMS AND THE RELIABILITY OF TECHNICAL MEANS

Background. The article substantiates the need for reliable fastening of wheeled equipment on an open railway platform with increasing loads and rolling stock speeds. Materials and methods. The technical means used for fastening wheeled vehicles during transportation and a new design of a device for accelerated fastening of equipment on a railway platform are considered. Results and conclusions. The possibility of increasing the reliability of accelerated fastening of wheeled vehicles on open rolling stock is shown by using elastic multi-turn chain fastenings in combination with lanyards for fastening, allowing them to be used for various wheel sizes. This fastening method is convenient, costeffective and reliable. The use of the proposed design of the brake system will reduce the wear of the friction surfaces of friction pairs, increase the service life by 1.2...1.3 times, compared with standard brakes of bogies of a substation car, and monitoring and diagnostics of the main parameters of railway equipment (systems) ) using sensors and control devices based on the use of modern non-contact measurement methods: laser, infrared, ultrasonic, fiber optic, etc. will improve the reliability of the substation. The use of a non-contact method for recording the profile of discs using a laser sensor and a scanning device will make it possible to obtain information about the parameters of the profile of the working surface of the brake discs of a railway wheel, including analysis of the complete profile of the brake discs and support of a wear database

QUALITY OF FORMING PARTS IN THE INTEGRATION OF HYBRID TECHNOLOGIES OF TRANSPORT ENGINEERING

Background. On the basis of system analysis, an approach is proposed for shaping parts of a complex configuration. It is shown that the complex application of traditional, additive and nanotechnologies for forming parts significantly improves the quality of surface formation. The relevance of the development of smart production systems is substantiated. Materials and methods. It is shown that the development of digital flexible production systems inevitably faces the introduction of additive technologies, robotic complexes, and partially traditional shaping tools, which opens up prospects for the synthesis of intelligent control systems for complex production systems. Results. The use of powder and composite materials, including nanomaterials, control of parameters and quality indicators must be ensured using intelligent control systems, which are based on modern non-contact, high-speed high-precision laser and fiber-optic sensors. Conclusions. The development of intelligent product quality management systems is impossible without the improvement of intelligent sensor systems that can facilitate data collection. Such sensors must have advanced interfaces and standardized data transmission formats

Equivalence of Mechanical and Magnetic Force in Magnetic Shape Memory Effect

High mobility of twin boundary is crucial for magnetic shape memory effect. The twin boundary can be moved by applied magnetic field or mechanical stress. In Ni-Mn-Ga 10M martensite there are two different, field movable, a-c twin boundaries type I and II due to monoclinic lattice. For single twin boundary of both types we experimentally evaluated the equivalence of magnetic and mechanical force and the validity of generally used energy model using direct stress-strain and magnetization measurements. For type II, highly mobile twin boundary, the equivalence seems to be valid and model broadly agrees with measurement. However, for type I the calculated magnetic stress is much larger than mechanical stress needed for twin boundary motion