A study of shrinkage percentage acrylonitrile butadiene styrene based on the ASTM D955 standard test method

Abstract

The shrinkage of plastic was caused by the shape of the product and the type of plastic used in the injection. The plastic shrinkage difference was resulted from the temperature used in melting, the injection speed, mold cooling and different injection surroundings. These led to unknown exact value of plastic shrinkage and the trial and error work has been done. As a result of trial and error work, the injection products were not in the determined size. This research aims to find the percentage of plastic shrinkage according to standard test ASTM D955 from (Amorphous Thermoplastic) (Acrylonitrile Butadiene Styrene, ABS). The findings showed that square specimen size 60x60x2 mm, measured from vertical perpendicular to flowing direction, the shrinkage was at 0.86%, the shrinkage was at 0.59% when measured from flowing direction and the thickness expanded at 20%. For the rectangular specimen size 12.7x127x3.2 mm, measured from vertical perpendicular to flowing direction, the expanding was at 0.16%, the shrinkage was at 0.88% when measured from flowing direction and the thickness expanded at 14.86%. The circular specimen size 100x3.2 mm, the shrinkage was at 1.26 when measured from vertical perpendicular to flowing direction, the shrinkage measured from flowing direction was at 0.82%, and the thickness expanded at 13.23%