Fracture structural materials

The Institute has many-year experience of investigations and developments in the field of NDT. These are, mainly, developments which allowed creation of a series of eddy current flaw detectors for various applications. The Institute has traditionally studied the physico-mechanical properties of materials, their stressed-strained state, fracture mechanics and developed on this basis the procedures and instruments which measure the properties and predict the behaviour of materials. Quite important are also developments of technologies and equipment for control of thickness and adhesion of thin protective coatings on various bases, corrosion control of underground pipelines by indirect method, acoustic emission control of hydrogen and corrosion cracking in structural materials, etc. 

Panasyuk V.V., Andreikiv A.V., Kovchik S.E. (1977) Methods of estimating the fracture toughness of structural materials. Kiev (in Russian). 

The intermetallic alloy NiAl is discussed as a potential base alloy for high temperature structural materials. Its use is currently limited by low room temperature ductility and fracture toughness. Consequently, substantial research efforts have been directed towards understanding its mechanical behaviour [1, 2] so that detailed experimental [3, 4, 5] and theoretical [6, 7, 8] analyses of the deformation of NiAl are available today. 

In general, molecular crystals are too soft for them to be of interest as structural materials. Also, they fracture readily. Because of their transparencies and non-linear properties some of them are of interest for optical applications, but most of them suffer from optical damage at low intensities of light. 

Fracture toughness (MPay ) Wollastonite 0.3-0.7 =0.3 Range of structural materials applications... 

Thus, modern methods of nonequilibrium mechanical tests do not allow identification of deformation and fracture conditions of concrete samples, which leads to an ambiguous evaluation of structural material properties, in particular, the crack resistance of a concrete. 

Tetelman, A. S. McEvily, A. J. "Fracture of Structural Materials" John Wiley New York, 1967. 

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