Metals strengthening

Mechanical alloying is another method of producing dispersion-strengthened metals. In this process, the powdered constituents of the ahoy are treated in an attrition mih. A finely distributed layer of the dispersed phase is distributed on particles of the base metal. Subsequent pressing and sintering strengthens the dispersion (25). 

Zukas, E.G., Shock-Wave Strengthening, Metals Engrg. Quart. 6, 1-20 (1966). 

The formation of solid solutions of metals is one way to change the properties (generally to increase strength) of the metals. Strengthening metals in this way is known as solid solution strengthening. The ability of two metals to form a solid solution can be predicted by a set of rules known as the Hume-Rothery rules, which can be stated as follows ... 

Precipitates have important effects on the mechanical, electronic, and optical properties of solids. Precipitation hardening is an important process used to strengthen metal alloys. In this technique, precipitates are induced to form in the alloy matrix by carefully controlled heat treatment. These precipitates interfere with dislocation movement and have the effect of hardening the alloy significantly. 

Strengthen metal panels by improving end connections, and reducing span of panels by adding girts and purlins. 

When the voids are filled with carbon atoms, the carbon helps hold the iron atoms in their lattice. This strengthened metal is called steel. 

The formula can also be used for dispersively strengthened metallic-nonmetallic composites, in which the host matrix is metal. 

Population of the lower / V I (bonding) portions of a band by electrons strengthens metallic bonding, whereas population of the upper (antibonding) portion of a band weakens metallic bonding. 

Alumina Fibers used to Strengthen Metals, Chem. Eng. News, 58(26), 24, June 30 (1980). 

Metal products are made by distinct manufacturing routes, leading to specific product forms to suit end-user needs. Fundamental differences between wrought, cast, powder metal and weld filler metals have led to different specification systems for such products. Heat treatment is the most important method of strengthening metals although mechanical work is also used. See Figure 5-1. 

Heat treatment is more widely used than cold work to strengthen metals because final properties can be tailored to design requirements and additionally achieve much higher strength levels. Not every metal may be heat treated. For example, the only way of strengthening austenitic stainless steels (300 series) is by cold work. 

Dislocations in ceramics can be pinned by solute atoms just as they can in metals as shown in Figure 17.14. The dislocations are impeded because of their interaction with the stress field around the impurity. This effect has long been used to strengthen metals. 

The decrease of the grain size d strengthens metallic alloys (Hall-Petch relationship, third term)... 

In Section 6.4, it was noted that the rate of water exchange decreases markedly as the charge on the metal ion increases and its size decreases. An increased charge-to-radius ratio is expected to strengthen metal-ligand bonds... 

Cadei J M C, Stratford T J, ffollaway L C and Ducket W G (2004), Strengthening metallic structures using externally bonded fibre-reinforced polymers C595 , London CIRIA. 

Cadei, J. M. C., et al. Strengthening metallic structures using externally bonded hbre-reinforced polymers (CIRIA Publication C595). London Construction Industry Research and Information Association, 2004. 

Another important way of strengthening metals is to alloy them with elements that are dissolved in the crystal lattice and form a solid solution. Such atoms... 

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