Mechanical properties of solids

Cars are not made of glass, and bottles are not made of steel, although cars and bottles may be made from polymers. The reasons for this are mostly bound up with the mechanical properties of the materials. These are controlled by two interacting features of the solid, the strength of the chemical bonds in the material, and the defects present. 

The strongest minerals are those with no weak bonds, but contain infinite three-dimensional networks of [SiOJ tetrahedra, linked to each other by all four vertices. Despite this strength, they often shatter and are britde. Metals, in contrast, although weaker in some ways, can be hammered into sheets (are malleable) or drawn into wires (are ductile) without breaking. 

Chemical bonding, however, is rarely directly responsible for the observed mechanical properties of a material. In fact, most sohds are far weaker than the strength predicted on the basis of the chemical bonds present. In these cases, the defects present, especially dislocations, stacking defects and grain boundaries, control matters. 

Materials reveal their mechanical properties when subjected to forces. The apphcation of a force results in a deformation. The amount of deformation will depend on the magnitude of the force and its direction measured with respect to the crystallographic axes. Both force and deformation are vector quantities. In the discussion below, it will be assumed that all materials are isotropic in this respect and that there is no crystallographic relationship between force and deformation, which are both presumed to be scalars (numbers. See section S4.13). In fact, in much of the discussion, especially of the elastic properties of sohds, the atomic structure is ignored, and the sohds are treated as if they were continuous. This viewpoint caimot explain plastic deformation, and knowledge of the crystal structure of the sohd is needed to understand the 

Understanding solids the science of materials. Richard J. D. Tilley 2004 John Wiley Sons, Ltd ISBNs 0 470 85275 5 (Hbk) 0 470 85276 3 (Pbk) 

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Ward I M 1971 Mechanical Properties of Solid Polymers (New York Wiley) p 329... 

H. J. Hoffman, Moisture Effects on Mechanical Properties of Solid Propellants, CPTR 84-29, CPIA Pubhcations, Johns Hopkins University, Laurel, Md., Feb. 1984. 

I. M. Ward, Mechanical Properties of Solid Polymers, John Wiley Sons, Inc., New York, 1971. 

W. Herrmann, D.L. Hicks, and E.G. Young, Attenuation of Elastic-Plastic Stress Waves, in Shock Waves and the Mechanical Properties of Solids (edited by J.J. Burke and V. Weiss), Syracuse University Press, Syracuse, 1971, pp. 23-63. 

Ward IM (1983) Mechanical properties of solid polymers. 2nd edn, John Wiley, Chichester, p 329... 

Mechanical properties of solid surfaces and thin hlms... 

Urban, M.W. 2005. Stimuli-Response Polymeric Films and Coatings. Oxford University Press, New York. Ward, I. and Sweeney, J. 2005. An Introduction to the Mechanical Properties of Solid Polymers. Wiley, Hoboken, NJ. 

I. M. Ward, Mechanical Properties of Solid Polymers, 2nd edn, John Wiley, New York (1983) A. E. Woodward, Understanding Polymer Morphology, Carl Hanser, Munich, Vienna (1995)... 

K. A. Gross, L.M. Rodriguez-Lorenzo, Sintered hydroxyfluorapatites. Part II Mechanical properties of solid solutions determined by microindentation, Biomaterials 25 (2004) 1385-1394. 

Dislocations are linear defects and were first invoked to account for the mechanical properties of solids, particularly the shear strengths. Dislocations play an important role in a variety of solid state phenomena from phase transitions to chemical reactions and the subject has been investigated and reviewed widely (Fine, 1973 Nembach, 1974). The effect of dislocations on the transformations and properties of organic solids has been recognized in recent years (Thomas Williams, 1971 Jones Thomas, 1979). 

There are, however, two other views which may be taken as to the purpose of experiments on the mechanical properties of solids those of the user and those of the materials scientist. First, the practical user of solids as load-bearing materials requires to... 

Phillips, Effects of Gamma Radiation from Cobalt 60 on the Mechanical Properties of Solid Propellants ALL and CDT , NPP-TMR-179, Naval Propint Plant, Indian Head (1960)... 

In the 1920s and 1930s, Rehbinder (Rehbinder and Likhtman, 1957) recognized that the presence of certain organic acids on the surfaces of solids resulted in a surface softening or a reduction in the mechanical properties of solids. The Rehbinder effect produced increases in plasticity in the presence of surface active materials. 

Polanyi, Ueber eine Art von Gittersto-rung. See E. Braun, Mechanical properties of solids in Lillian Hoddeson et al Out of the Crystal Maze Chapters from the History of Solid-State Physics (New York Oxford University Press, 1992), 317-358, on 327-331. 

Time-dependent Mechanical Properties of Solid Bodies... 

Kustov A.I. (1994) Study of structure and physical-mechanical properties of solid materials by the acoustomicroscope methods // Materials of VII Rus. conf. Damped materials , P. 89-97. 

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