List of Important Alloys and their Composition: (1) Aluminium Alloys (2) Copper Alloys (3) Magnesium Alloys (4) Nickel Alloys (5) Steel Alloys. (1) Aluminium Alloys: These are preferred to pure aluminium for constructional purposes. They are hard and strong. They contain copper, silicon, magnesium, manganese, iron and nickel in various combinations. Following are the important alloys of aluminium: (i) Aldural [...]
In this article we will discuss about the solidification of polycrystalline materials with its schematic diagram. A space lattice is formed by adding unit cells one after the other in three dimensions. It is possible to produce a macroscopic visible piece of a metal, formed by repetition of unit cells of crystal structure of that metal in three dimensions of [...]
In this article we will discuss about the shapes of phases with its diagram. Any surface or an interface such as a grain boundary has energy related with it, which acts like a surface tension. A solid phase does not easily change its shape in response to the surface tension (due to rigid bonds between atoms in a solid), unless [...]
A substance which is composed of two or more chemical elements such that metallic atoms predominate in composition and the metallic bond predominates is called an alloy. The element present in largest proportion is called the "base metal" and all other elements present are known as "alloying elements". Alloying elements can drastically change, (improve) physical, chemical, mechanical and electrical properties [...]
In a eutectic reaction, when a liquid solution of fixed composition, solidifies at a constant temperature, forms a mixture of two or more solid phases without an intermediate pasty stages. This process reverses on heating. In a eutectic system, there is always a specific alloy, known as 'eutectic composition' that freezes at a lower temperature than all other compositions. At [...]
An alloy may be defined as coherent metallic mass produced by the intimate association of two or more metals. In some cases also the introduction of non-metals such as carbon, silicon, phosphorus, boron, sulphur and even nitrogen or oxygen may produce marked effects. It is important that thousands of combinations resulting in useful alloys are possible. Important non-ferrous alloys are [...]
The decomposition of SSSS during ageing is usually a complex process. The equilibrium precipitate, θ, normally does not form directly from the SSSS at commonly used ageing temperatures, because the nucleation barrier for its formation is too high (i.e., large energy is needed because of the surface energy required to create the surface of the critical-sized precipitate). The precipitation occurs [...]