ASTM D955-08
Standard Test Method of Measuring Shrinkage from Mold Dimensions of Thermoplastics
- Standard No.
- ASTM D955-08
- Release Date
- 2008
- Published By
- American Society for Testing and Materials (ASTM)
- Status
- Replace By
- ASTM D955-08(2014)
- Latest
- ASTM D955-21
- Scope
- p>Injection Molding8212;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 D 3641
or ISO 294-4 or the appropriate material specification will improve the reproducibility of the test. Compression Molding8212;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 D 4703
or ISO 293 or the appropriate material specifications will improve the reproducibility of the test. 1.1 This test method is intended to measure shrinkage from mold cavity to molded dimensions of thermoplastics when molded by compression or injection processes with specified process conditions.
1.2 This test method covers shrinkage measurements at 24 and 48 h.
1.3 This method will give comparable data based on standard specimens and can not predict absolute values in actual molded parts with varying flow paths, wall thicknesses, pressure and temperature gradients and process conditions. Differences in mold shrinkage may also be observed among the three specimen geometries described in this test method.
1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are given for information only.
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
Note 18212;This standard and ISO 294-3 are equivalent in the design of specimen D2. This test method is equivalent to ISO 294-4 where Type D2 specimens and the procedure in Appendix X2 are used.
ASTM D955-08 Referenced Document
- ASTM D3641 Standard Practice for Injection Molding Test Specimens of Thermoplastic Molding and Extrusion Materials
- ASTM D4066 Standard Classification System for Nylon Injection and Extrusion Materials (PA)
- ASTM D4549 Standard Classification System and Basis for Specification for Polystyrene and Rubber-Modified Polystyrene Molding and Extrusion Materials (PS)
- ASTM D4703 Standard Practice for Compression Molding Thermoplastic Materials into Test Specimens, Plaques, or Sheets
- ASTM D4976 Standard specifications for polyethylene plastic molding and extrusion materials*， 2024-04-19 Update
- ASTM D5947 Standard Test Methods for Physical Dimensions of Solid Plastics Specimens
- ASTM D618 Standard Practice for Conditioning Plastics for Testing
- ASTM D6778 Standard Classification System and Basis for Specification for Polyoxymethylene Molding and Extrusion Materials (POM)
- ASTM D6779 Standard Classification System for and Basis of Specification for Polyamide Molding and Extrusion Materials (PA)
- ASTM D788 Standard Classification System for Poly(Methyl Methacrylate) (PMMA) Molding and Extrusion Compounds
- ASTM D883 Standard Terminology Relating to Plastics
- ASTM E691 Standard Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
- ISO 293 Plastics — Compression moulding of test specimens of thermoplastic materials
- ISO 294-1 Plastics - Injection moulding of test specimens of thermoplastic materials - Part 1: General principles, and moulding of multipurpose and bar test specimens
- ISO 294-3 Plastics — Injection moulding of test specimens of thermoplastic materials — Part 3: Small plates
- ISO 294-4 Milling cutters mounted on centring arbors having a 7/24 taper; Fitting dimensions; Centring arbors
ASTM D955-08 history
- 2021 ASTM D955-21 Standard Test Method of Measuring Shrinkage from Mold Dimensions of Thermoplastics
- 2008 ASTM D955-08(2014) Standard Test Method of Measuring Shrinkage from Mold Dimensions of Thermoplastics
- 2008 ASTM D955-08 Standard Test Method of Measuring Shrinkage from Mold Dimensions of Thermoplastics
- 2000 ASTM D955-00 Standard Test Method of Measuring Shrinkage from Mold Dimensions of Thermoplastics
- 1989 ASTM D955-89(1996) Standard Test Method of Measuring Shrinkage from Mold Dimensions of Thermoplastics
