Standard Test Method of Measuring Shrinkage from Mold Dimensions of Thermoplastics

Importancia y uso:

5.1 Injection Molding—In injection molding, the difference between the dimensions of a mold cavity and of the molded specimen may vary according to the design of the mold and operation of the molding process. Factors such as mold and melt temperature, fill times, and packing conditions are known to affect shrinkage significantly. Adherence to the specified mold design (see 7.1) and specifications outlined in Practice D3641 or ISO 294-4 or the appropriate material specification will improve the reproducibility of the test.

5.2 Compression Molding—In compression molding, the difference between the dimensions of a mold cavity and of the molded specimen may vary according to the design of the mold and operation of the molding process. Factors, such as the amount of material in charge, cooling time, and pressure application are known to affect shrinkage significantly. Adherence to the specified mold design (see 7.2) and specifications outlined in Practice D4703 or ISO 293 or the appropriate material specifications will improve the reproducibility of the test.

Subcomité:

D20.09

Referida por:

F2042-18, D3641-24, F0997-18, D4000-23, F0665-09R24

Volúmen:

08.01

Número ICS:

83.140.10 (Films and sheets)

Palabras clave:

mold shrinkage; shrinkage; thermoplastics;