What these societies do is standardize the definition of alloys That is to say

What these societies do is standardize the definition

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What these societies do is standardize the definition of alloys. That is to say, they write the recipe for alloy manufacturers to use in order to make alloys. Take stainless steel for instance. First of all there are different grades (or recipes) of stainless steel, with 304 and 316 being the most common prescribed by the ASTM. If you order 316, the steel manufacturer will melt iron and add various amounts of carbon, chromium, and other metals as per the ASTM specification. Then, depending on the properties you want, the manufacturer will allow the steel to harden at a certain cooling rate and form it into the shape you want delivered to your place of business. They may also do post processing (after the shaping) treatments like stress relieving or stress hardening to again give you different properties for your steel. REASONS FOR ALLOYING The best reason for making a metal alloy is to make a stronger material, the choice example being steel. Iron is a main component in steel, but by itself it is weaker than the steel alloy. Another reason for making an alloy is to make something less expensive. Coins, for example, used to be made with more "pure" materials, but the natural supply of the highly valuable metals is not enough for the amount of coins that are produced. Less precious materials are added, which reduces the worth of the coin but also allows more production. MIXTURES o The composition of a mixture is variable. o Each of its components retains its characteristic properties. o Its components are easily separated by physical means. COMPOUNDS o The relative proportions of the elements in a compound are fixed.
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~ Page 61 of 79 ~ Example- 2 atoms of hydrogen + 1 atom of oxygen becomes 1 molecule of compound-water. o The components of a compound do not retain their individual properties. Both sodium and chlorine are poisonous; their compound, table salt (NaCl) is absolutely essential to life. Example- Hydrogen (element {which is combustible and non-supporter of combustion}) + Oxygen (element {which is non-combustible and supporter of combustion}) becomes Water (compound {which is non-combustible and non-supporter of combustion}). o It takes large inputs of energy to separate the components of a compound. Compounds Compared to Mixtures The physical and chemical properties of compounds are different from those of their constituent elements. This is one of the main criteria for distinguishing a compound from a mixture of elements or other substances because a mixture's properties are generally closely related to and dependent on the properties of its constituents. Another criterion for distinguishing a compound from a mixture is that the constituents of a mixture can usually be separated by simple, mechanical means such as filtering, evaporation, or use of a magnetic force, but the components of a compound can only be separated by a chemical reaction.
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