ASTM D6289-03

Standard Test Method for Measuring Shrinkage from Mold Dimensions of Molded Thermosetting Plastics

SCOPE
1.1 This test method is intended to measure shrinkage from mold cavity to molded dimensions of thermosetting plastics when molded by compression, injection, or transfer under specified conditions.
1.2 This test method provides for the measurement of shrinkage of thermosetting plastics from their molds both initially (within 16 to 72 h of molding) and as they age (post-shrinkage at elevated temperatures).
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 gradiants and process conditions. Differences in mold shrinkage generally is observed between the specimen geometries described in this test method.
1.4 Knowledge of the initial shrinkage of plastics is important for the construction of molds and knowledge of post molding shrinkage is important for determining the suitability of the molding material for manufacturing thermosetting plastic components with accurate dimensions.
1.5 The values stated in SI units are to be regarded as the standard. The values given in brackets are for information only.
1.6 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 1—This test method and ISO 2577-1984 are equivalent when bars of 120 mm length, 15 mm width, and 10 mm thickness are used for compression molding; or flat, square plaques approximately 120 by 120 by 4 mm are used for injection molding.

General Information

• Status: Historical
• Publication Date: 31-Oct-2003
• ICS: 83.080.10 - Thermosetting materials
• Technical Committee: D20 - Plastics
• Drafting Committee: D20.09 - Specimen Preparation

Relations

• Replaces: ASTM D6289-98 - Standard Test Method for Measuring Shrinkage from Mold Dimensions of Molded Thermosetting Plastics
• Effective Date: 01-Nov-2003
• Replaced By: ASTM D6289-08 - Standard Test Method for Measuring Shrinkage from Mold Dimensions of Molded Thermosetting Plastics
• Effective Date: 15-Apr-2008
• Referred By: ASTM D704-99(2020) - Standard Specification for Melamine-Formaldehyde Molding Compounds
• Effective Date: 01-Nov-2003

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation:D6289–03
Standard Test Method for
Measuring Shrinkage from Mold Dimensions of Molded
1
Thermosetting Plastics
This standard is issued under the fixed designation D 6289; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope* D 618 Practice for Conditioning Plastics and Electrical
Insulating Materials for Testing
1.1 This test method is intended to measure shrinkage from
D 796 PracticeforCompressionMoldingTestSpecimensof
mold cavity to molded dimensions of thermosetting plastics
Phenolic Molding Compounds
when molded by compression, injection, or transfer under
D 883 Terminology Relating to Plastics
specified conditions.
D 1896 Practice for Transfer Molding Test Specimens of
1.2 This test method provides for the measurement of
Thermosetting Compounds
shrinkage of thermosetting plastics from their molds both
D 3419 PracticeforIn-lineScrew-InjectionMoldingofTest
initially (within 16 to 72 h of molding) and as they age
Specimens from Thermosetting Compounds
(post–shrinkage at elevated temperatures).
D 5224 Practice for Compression Molding Test Specimens
1.3 This method will give comparable data based on stan-
of Thermosetting Molding Compounds
dard specimens and can not predict absolute values in actual
E 691 Practice for Conducting an Interlaboratory Study to
molded parts with varying flow paths, wall thicknesses, pres-
Determine the Precision of a Test Method
sure gradiants and process conditions. Differences in mold
3
2.2 ISO Standards:
shrinkage generally is observed between the specimen geom-
ISO 291 Plastics—Standard Atmospheres for Conditioning
etries described in this test method.
and Testing
1.4 Knowledge of the initial shrinkage of plastics is impor-
ISO 295 Plastics—Compression Molding Test Specimens
tant for the construction of molds and knowledge of post
of Thermosetting Materials
molding shrinkage is important for determining the suitability
ISO 10724 Plastics—Thermosetting Molding Materials—
of the molding material for manufacturing thermosetting plas-
Injection Molding of Multipurpose Test Specimens
tic components with accurate dimensions.
ISO 2577-1984 Plastics—Thermosetting Moulding
1.5 The values stated in SI units are to be regarded as the
Materials—Determination of Shrinkage
standard.Thevaluesgiveninbracketsareforinformationonly.
1.6 This standard does not purport to address all of the
3. Terminology
safety concerns, if any, associated with its use. It is the
3.1 General—Definitions of terms applying to this test
responsibility of the user of this standard to establish appro-
method appear in Terminology D 883.
priate safety and health practices and determine the applica-
3.2 Definitions—For the purpose of this test method, the
bility of regulatory limitations prior to use.
following definitions apply:
NOTE 1—This test method and ISO 2577-1984 are equivalent when
3.2.1 molding shrinkage—the difference in dimensions be-
bars of 120 mm length, 15 mm width, and 10 mm thickness are used for
tween a molding and the mold cavity in which it was molded,
compression molding; or flat, square plaques approximately 120 by 120
both the mold and the molding being at 23 6 2°C when
by 4 mm are used for injection molding.
measured.
2. Referenced Documents 3.2.2 post-shrinkage—shrinkage of a plastic product after
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molding, during post-treatment, storage or use.
2.1 ASTM Standards:
4. Significance and Use
1
This test method is under the jurisdiction ofASTM Committee D20 on Plastics 4.1 Compression Molding—In compression molding, the
and is the direct responsibility of Subcommittee D20.09 on Specimen Preparation.
differencebetweenthedimensionsofamoldandofthemolded
Current edition approved November 1, 2003. Published January 2004. Originally
article produced therein from a given material vary according
approved in 1998. Last previous edition approved in 1998 as D 6289 - 98.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
3
Standards volume information, refer to the standard’s Document Summary page on Available from American National Standards Institute (ANSI), 25 W. 43rd St.,
the ASTM website. 4th Floor, New York, NY 10036.
*A Summary of Changes section appears at the end of this standard.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
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D6289–03
to the design and operation of the mold. It is probable that 6. Apparatus
shrinkage will approach a minimum where design and
...