Mechanical Properties of Metals

Table 3-1 Examples of the mechanical properties of metal and plastic materials...

R. P. Jewett, Effect of Gaseous Hydrogen on the Mechanical Properties of Metals Used in the Petroleum... 

Owing to hydrogen embrittlement, the mechanical properties of metallic and nonmetal-lic materials of containment systems may degrade and fail resulting in leaks. Hydrogen embrittlement depends on many factors such as environmental temperature and pressure, purity of metal, concentration and exposure time to hydrogen, stress state, physical and mechanical properties, microstructure, surface conditions, and the nature of the crack front of material [23]. 

The main considerations of mechanical properties of metals and alloys at low temperatures taken into account for safety reasons are the transition from ductile-to-brittle behavior, certain unconventional modes of plastic deformation, and mechanical and elastic properties changes due to phase transformations in the crystalline structure. 

Chandler, W.T. and Walter, R.J., Testing to determine the effect of high pressure hydrogen environments on the mechanical properties of metals, in Hydrogen Embrittlement Testing ASTM 543, American Society for Testing and Materials, Philadelphia, PA, 1974, p. 170. 

In the 1950 s an investigation into the effect of ultrasonic vibrations on the mechanical properties of metals showed that superimposing an alternating stress on a workpiece greatly affected the process rate and considerably reduced the force necessary for work-piece deformation [20]. 

Friedel, J. proc. Int. School of Physics Enrico Fermi, course LXI, Atomic Structure and Mechanical Properties of Metals , (ed. G. Gagliotti) North Holland 1976... 

After a somewhat lengthy introduction into the theoretical and experimental aspects of mechanical properties, which we will see apply to all material classes, we come finally to the specifics of mechanical properties of metals and alloys. 

The effect of dispersoids on the mechanical properties of metals has already been described in Section 5.1.2.2. In effect, these materials are composites, since the dispersoids are a second phase relative to the primary, metallic matrix. There are, however, many other types of composite materials, as outlined in Section 1.4, including laminates, random-fiber composites, and oriented fiber composites. Since the chemical nature of the matrix and reinforcement phases, as well as the way in which the two are brought together (e.g., random versus oriented), vary tremendously, we shall deal with specific types of composites separately. We will not attempt to deal with all possible matrix-reinforcement combinations, but rather focus on the most common and industrially important composites from a mechanical design point of view. 

In this method of study there are two important steps in the preparation of the specimen. The first is the growth of the single crystal itself, and the second is the preparation of the surface. Large single crystals of metals have been used for about fifty years largely for the study of physical and mechanical properties of metals, and it is only recently with the advent of electrolytic polishing that it has been possible to use them for the study of reactions between metals and gases. 

A change in the surface tension does not exert essential influence on the mechanical properties of metals and vice versa however, a significant decrease in surface tension caused by adsorption should promote corrosion (Kolotyrkin, 1967). Plastic deformation can arise at the site of the stress concentrations, i.e., notches, asperities, scratches, inclusions and surface irregularities (Chiu, 1999). 

W.C. Roberts-Austen On certain mechanical properties of metals considered in relation to the periodic law. Philos. Trans. Roy. Soc. Lond. A 179, 339-349 (1888)... 

J. S. Benjamin, C. B. Raymond, Nickel-Based Dispersion-Strengthened Alloys, in Mechanical Properties of Metallic Composites Ochiai, S., Ed. Marcel Dekker, 1993. 

The mechanical properties of metals and alloys are of the greatest practical importance, more so than in other groups. 

The thermodynamic driving force for interface creation for clean metal-metal systems, defined in terms of the work of adhesion, is invariably large as shown in Chapter 5 and hence generates the expectation that the mechanical properties of metal-metal interfaces will be excellent. This is usually observed in practice when wetting produces complete and intimate contact of the braze and component... 

The concept of a defect has undergone considerable evolution over the course of the last century. The simplest notion of a defect is a mistake at normal atom site in a solid. These stmcturally simple defects are called point defects. Not long after the recognition of point defects, the concept of linear defects, dislocations, was invoked to explain the mechanical properties of metals. In later years, it became apparent that planar defects, including surfaces, and volume defects such as rods, tubes, or precipitates, also have important roles to play in influencing the physical and chemical properties of the host matrix. More recently, it has become apparent that interactions between point defects are of considerable importance, and the simple model of isolated point defects is often inadequate with... 

Mechanical Properties of Metallic Composites, edited by Shojiro Ochiai... 

Chemical or extractive metallurgy is concerned with the extraction of metals from ores and with the refining of metals. Physical metallurgy is concerned with the physical and mechanical properties of metals as affected by composition, mechanical working, and heat treatment. 

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