powder metallurgy

Powder metallurgy is a means of manufacturing, without full melting, objects having properties which cannot be obtained by any other process. It is a technique that is applied for consolidation and formation of materials into useful products with different shapes, starting with powder mass. Powder metallurgy has played a vital role in solving many production problems, especially with those materials having very high melting points. During the last period of time powder technology has made remarkable progress for many fundamental reasons:
(i) It can be used to manufacture articles which cannot be made by any other route, such as porous bearing, filters, abrasive tools, electric lamp filaments, dynamo brushes, and a variety of soft and hard magnets, etc.
(ii) High purity material can be produced through this technique by controlling the production processes.(iii) It may be used for products which may be made by other methods, but for which powder metallurgy is more convenient and cheaper with better quality. The development of powder metallurgy is due to its great advantages over other routes in certain applications. It has now become the basis for the production of refractory metals, heat resistances materials, cutting tools, especial alloys which cannot be produced by conventional melting method, ceramic materials and most of magnets either in micro-scales or in nano-scales. The aim of this article is to give a general idea about powder metallurgy and its employment in the production of permanent magnets with especial specification according to their use.