Sintering and Powder Compaction

According to an early historical overview (Jones 1960), the numerous attempts to understand the sintering process in both ceramics and metals fall into three periods (1) speculative, before 1937 (2) simple, 1937-1948 (3) complex, 1948 onwards. The complex experiments and theories began just at the time when metallurgy underwent its broad-based quantitative revolution (see Chapter 5). 

This experiment is discussed here in some detail both beeause it casts light on the driving force for sintering and because it is a beautiful example of the ingenious 

Several of the early studies aimed at finding the governing mechanisms of sintering were done with metal powders. A famous study was by Kuczynski (1949) who also examined the sintering of copper or silver to single-crystal metal plates but 

In the same year as Kuezynski s research was published, Shaler (1949), who had done excellent work on measuring surface energies and surface tensions on solid metals, argued that surface tension must play a major part in fostering shrinkage of powder compacts during sintering his paper (Shaler 1949) led to a lively discussion, a feature of published papers in those more spacious days. 

The chemistry of ceramics plays a role in their behaviour during sintering. Nonstoichiometry of oxides has been found to play a major role in the extent to which a 

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