Mechanical magnetic properties

Interest is maintained ia these materials because of the combination of mechanical, corrosion, electric, and magnetic properties. However, it is their ferromagnetic properties that lead to the principal appHcation of glassy metals. The soft magnetic properties and remarkably low coercivity offer tremendous opportunities for this appHcation (see Magnetic materials, bulk Magnetic materials, thin film). 

Material property specifications must be written by design and material engineers to control engineering requirements and to control incoming raw material quahty. Material property requirements depend on various ia-use functional needs ia terms of electrical, mechanical, thermal, chemical, optical, and magnetic properties. 

Thin-film XRD is important in many technological applications, because of its abilities to accurately determine strains and to uniquely identify the presence and composition of phases. In semiconduaor and optical materials applications, XRD is used to measure the strain state, orientation, and defects in epitaxial thin films, which affect the film s electronic and optical properties. For magnetic thin films, it is used to identify phases and to determine preferred orientations, since these can determine magnetic properties. In metallurgical applications, it is used to determine strains in surfiice layers and thin films, which influence their mechanical properties. For packaging materials, XRD can be used to investigate diffusion and phase formation at interfaces... 

David Turnbull, in his illuminating Commentary on the Emergence and Evolution of Materials Science (Turnbull 1983), defined materials science broadly as the characterisation, understanding, and control of the structure of matter at the ultramolecular level and the relating of this structure to properties (mechanical, magnetic, electrical, etc.). That is, it is Ultramolecular Science . In professional and educational practice, however, he says that materials science focuses on the more complex features of behaviour, and especially those aspects controlled by crystal... 

Of the many properties of films in their successive stages, those most commonly studied nowadays are the magnetic, electrical and mechanical ones. The magnetic properties and uses of thin films, especially multilayers, have been outlined in Section 7.4 and need not be repeated here however, it is worth pointing out an excellent survey of magnetic multilayers (Grunberg 2000). Electrical properties have been covered by Coutts (1974). 

Numerous AFM imaging techniques have been developed and commercialized to monitor topography, friction, mechanical response, capacitance, magnetic properties, etc. However, adhesion measurements require the tip to come into, and out of, contact to measure attractive and adhesion forces. Therefore, other than to select an analysis region, most imaging techniques are not useful for adhesion studies. Instead, measurements are necessarily based on force-displacement curve approaches. 

In addition to nickel alloys, nickel also forms an important alloying element in stainless steels and in cast irons, in both of which it confers additional corrosion resistance and improved mechanical and engineering properties, and in Fe-Ni alloys for obtaining controlled physical and magnetic properties (see Chapter 3). With non-ferrous metals nickel also forms important types of alloys, especially with copper, i.e. cupro-nickels and nickel silvers these are dealt with in Section 4.2. 

The general theory of the quantum mechanical treatment of magnetic properties is far beyond the scope of this book. For details of the fundamental theory as well as on many technical aspects regarding the calculation of NMR parameters in the context of various quantum chemical techniques we refer the interested reader to the clear and competent discussion in the recent review by Helgaker, Jaszunski, and Ruud, 1999. These authors focus mainly on the Hartree-Fock and related correlated methods but briefly touch also on density functional theory. A more introductory exposition of the general aspects can be found in standard text books such as McWeeny, 1992, or Atkins and Friedman, 1997. As mentioned above we will in the following provide just a very general overview of this... 

In their pursuit of determining solution structures of dinuclear copper complexes as carried out for complex (29) (Section 6.6.3.1.1). Comba reported complex (431) (r = 0.02 Cu-Cu 6.9 A, comparable with the values of 7.2 A predicted by molecular mechanics calculations and 6.7 A obtained from the simulated EPR spectrum).54 They reported369 complexes (432) (square planar) and (433) (Cu-Cu 3.35 A) as well. As part of studying magnetic properties of mono-, di-, and... 

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