Today is May 11, tomorrow is May 12 is the International Nurses Day, and the day after tomorrow it is the annual Mother's Day. Dongguan Plastic mold factory of the majority of your colleagues how you want to go before? First of all, no matter how friends, today editors to introduce the plastic mold thermosetting plastic process performance - shrinkage.
First of all to introduce the reasons for the occurrence of shrinkage, plastic is usually in a certain degree of pressure under pressure forming, when cooling to the room when the size of the main changes in accordance with the principle of heat shrinkage shrinkage, this performance is called plastic Contraction.
The basic factors that affect contraction
(1) the type of plastic
(2) changes in chemical structure
(3) heat shrinkage
(4) elastic recovery
(5) molding process
(6) molding process
(7) plastic deformation
(8) other factors (residual stress caused by plastic parts of the retraction is called after the shrinkage of plastic products in the need for heat treatment after forming, heat shrinkage caused by heat treatment known as post-processing shrinkage.)
The vast majority of plastic, molding shrinkage in the order of 10-3 ~ 10-2, rarely in the order of 10-4, the following is common:
Polyethylene (1.5 to 3.5) x10-2
Polycarbonate (0.5 to 0.7) x10-2
Nylon 6 (0.6 ~ 1.6) x10-2
POM (2 ~ 2.5) x10-2
Nylon 1010 (1.0 to 2.5) x10-2
PET (containing 15 to 40% glass fiber) (0.8 to 0.9) x10-2
Note: The above information from the Jiezheng mold finishing the Internet, welcome reproduced, indicate the source!