Magnetic method

A Magnetic Method for Testing of High Strength Bolts. 

Distribution of the relativ body force (RF) on 1127 bolts determined by the magnetic method and 42 bolts out of this number found faulty by the DIN method. 

The publication of interstate Standard GOST 30415-96" Steel. Non-destructive inspection of mechanical properties and microstructure of metal products by magnetic method" - is the long-expected event for works laboratories and development engineers of non-destructive test means. 

The Standard covers bar, plates, sheets, strip, structural shapes rolled stock, pipes, sheets with laminar coating and strip of carbon, alloyed and electrical steels and sets up nondestructive magnetic method of mechanical and service properties and microstructure control. 

Not to overload the Statidard, three supplements are predetermined for it. The Supplement A (compulsory ) with the list of statistics is due to compulsory determination by non-destructive magnetic method of mechanical properties test. This Supplement provided the possibility to set the reasonable compromise between two opposite tendencies -to simplify utmost a body of mathematics or, on the contrary, to complicate it to such extent that it becomes inaccessible. 

It is known that diagram " Stress - Deformation " ( SD) is more vividly specifying the current metalwork condition. However, such diagram can be obtained only by destructive testing. The suggested non-destructive magnetic method in the report for the evaluation of SD condition and for the prediction of residual resource of metalwork, where the measurement of coercive force (CF) is assumed as a basis. 

Magnetic Method for Nonmagnetic Coatings on Magnetic Basis Metals... 

Magnetic Method for Nickel Coatings on Magnetic and Non-magnetic Substrates... 

Zinc coatings are covered by an ASTM specification (143). Because of the varying purity of 2inc deposits from chloride and 2incate baths, some thickness measuring methods can vary considerably (39). Methods based on physical measurement of magnetic methods (144,145) are used for best accuracy. 

Let us take 1978 as the starting point. Massoth [51] then published an extensive review of what was known about the structure of HDS catalysts. Characterization was essentially based on techniques such as X-ray diffraction, electron microscopy, photoelectron spectroscopy, electron spin resonance and magnetic methods. Massoth was rather unhappy with the state of affairs in 1978. He was struck by the ...diversity and apparent contradictions of results and interpretations... It almost seems as though everyone is working with a different catalyst . 

Dr A.N. Dremin of Institute of Chemical Physics, Moscow, stated that Zavoyskii suggested a direct magnetic method for measurement of particle velocity behind the shock front in the transition region. A metal foil (ca 0.03 mm in thickness) is placed in the explosive to test and the charge is then placed in the magnetic field. 

The magnetic method cannot be applied to tripositive chromium, the structures of the two extreme types having the same number of unpaired electrons and entering into resonance with each other. The chemical properties of the chromium complexes indicate that chromium, like the other iron-group elements, forms hyperligating bonds... 

Blitz, J. Electrical Magnetic Methods of Nondestructive Testing, Institute of Physics Publishing, London, UK. 1991. 

Advanced monitoring methodologies (gas detectors, infrared monitoring, thickness measurements by eddy current and magnetic methods)... 

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