Today's KNOWLEDGE Share: Shrinkage

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Today's KNOWLEDGE Share:

Shrinkage is sometimes explained simply in terms of CTE (coeff. of thermal expansion). The plastics cool down from melt to room T, hence... it shrinks.


In the Injection Molding process however we take advantage of melt compressibility and fairly high pressure (the packing) to compensate for the natural shrinkage of the material.


The result is that, although you can't change the coefficient of thermal expansion with your process, you ABSOLUTELY can change the final shrinkage of your part, almost at will !


Source:Vito Leo

Visit MY BLOG http://polymerguru.blogspot.com


#plastics #polymerindustry #injectionmolding #shrinkage #expansion

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