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POWDER PROCESSING:
Powder processing forms solid parts from material powders. It has been claimed powder metallurgy was used by the Egyptians 5000 years ago and in India 2,000 years ago, both in the manufacture of iron parts. Modern powder processing techniques began in the early 1800 s. Powder processing saw widespread use, in industrial manufacturing, in the early 1900 s in the production of Tungsten light bulb filaments. Modern industry employs many different powder processes. Parts from 50-100 lbs can be produced as the upper size limit typical in powder metallurgy. Most parts produced by these types of methods, however, tend to be under 5 lbs. Design and applications of powder processes are discussed in this section.
Design Of Powder Processes
Powder processes are suited to a specific and somewhat limited range of manufacturing applications. Due to the nature of powder metallurgy, a unique set of design considerations exist. In general, compaction and ejection from the die as well as powder flow during compaction are primary factors influencing the design of powder processes. Tooling is an integral factor in manufacturing process design. For example, parts requiring long thin punches should be avoided, since punch rigidity is critical.