Presintering is an operation in which the powder metallurgy components after compaction are heated for a short time to a temperature considerably below the final sintering temperature. The purpose of the intermediate operation is to strengthen the green compact for handling and subsequent operations.
Presintering is necessary to produce parts from material such as tungsten carbide which become very hard on sintering. When machining is required to be done on such parts, the problem is alleviated by employing a presintering operation. The machined parts are then finally sintered. As there is very little dimensional change on final sintering, in most cases no further work is required to be done on these parts. If no machining is required presintering can be eliminated.