Transfer molding
in transfer molding, the thermosetting powder or performs are placed into a separate well or pressure chamber above the mold cavities.Here the material is plasticized by heat and pressure and injected into the mold cavities as a hot liquid, where it is cured and becomes hard.The curing time for transfer molding is generally less than required for compression molding.The loading time is also shortened since larger performs are used which can be heated more rapidly.
(manufacturing processes Myron L.Begeman 1969 p.672)
Injection molding of thermoplastics
injection molding machines are somewhat similar to those used for die casting.Thermoplastic material is converted from a granular material to a liquid and then injected into a mold where it solidifies.This material can be repeatedly changed from solid to liquid without any chemical change, making it ideal for rapid processing. (manufacturing processes Myron L.Begeman 1969 p.673)
Elevated temperature machining
When the workpiece is heated, the shear strength of the metal is reduced, and the plastic deformation ahead of the cutting tool is accomplished with less power.The chips formed tend to be continuous, and the Cincinnati milling machine company has found that the temperature at the tool-chip interface does not increase in proportion to the temperature of the workpiece.Tool life is increased and cutting speeds may be doubled. (manufacturing processes Myron L.Begeman 1969 p.654)
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