Blending and Mixing of Powders
For successful results in compaction and sintering, the starting powders must be homogenized
Blending - powders of same chemistry but possibly different particle sizes are
intermingled
◦ Different particle sizes are often blended to reduce porosity
Mixing - powders of different chemistries are combined
Compaction
Application of high pressure to the powders to form them into the required shape
Conventional compaction method is pressing, in which opposing punches squeeze the
powders contained in a die
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The workpart after pressing is called a green compact, the word green meaning not yet
fully processed
The green strength of the part when pressed is adequate for handling but far less than
after sintering
กระบวนการกดแบบดั้งเดิม (Conventional Pressing in PM