ASTM D6491-09

Standard Practice for Evaluation of Aging Resistance of Prestressed Prepainted Metal In a Dry Heat Test

ABSTRACT
This practice details the standard procedure for evaluating the resistance of prestressed prepainted metal panels to cracking, or loss of adhesion, or both, after accelerated heat aging by dry heat test. This test method requires the use of gravity or forced air laboratory oven, bench vise, bending dies or test shims, 10x magnifier, and adhesive tape.
SCOPE
1.1 This practice can be used to evaluate the resistance of a prestressed prepainted metal panel to cracking, or loss of adhesion, or both, after accelerated heat aging. Most coil coated products are formed and bent into specific shapes to produce a final product. These operations introduce stresses, which may be relieved by cracking of the coating after aging.
1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.
1.3 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.

General Information

• Status: Historical
• Publication Date: 31-May-2009
• ICS: 87.020 - Paint coating processes
• Technical Committee: D01 - Paint and Related Coatings, Materials, and Applications
• Drafting Committee: D01.53 - Coil Coated Metal

Relations

• Replaces: ASTM D6491-99(2003) - Standard Practice for Evaluation of Aging Resistance of Prestressed Prepainted Metal In a Dry Heat Test
• Effective Date: 01-Jun-2009
• Referred By: ASTM D3794-22 - Standard Guide for Testing Coil Coatings
• Effective Date: 01-Jun-2009

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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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: D6491 − 09
Standard Practice for
Evaluation of Aging Resistance of Prestressed Prepainted
1
Metal In a Dry Heat Test
This standard is issued under the fixed designation D6491; 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 (´) indicates an editorial change since the last revision or reapproval.
1. Scope 4. Test Specimens
1.1 This practice can be used to evaluate the resistance of a
4.1 Cut samples 75 mm (3 in.) wide (across the bend
prestressed prepainted metal panel to cracking, or loss of direction) by whatever length is necessary to make the appro-
adhesion, or both, after accelerated heat aging. Most coil
priate number of bends. The direction of the bend may be
coated products are formed and bent into specific shapes to transverse or longitudinal to the “rolling direction” of the
produce a final product. These operations introduce stresses,
metal—or as agreed upon between customer and vendor.
which may be relieved by cracking of the coating after aging.
5. Procedure
1.2 The values stated in SI units are to be regarded as the
standard. The values given in parentheses are for information
5.1 Perform the fabrication at room temperature, 25 6 1°C
only.
(77 6 2°F). All test specimens should be equilibrated to the
same temperature before fabricating. Different fabrication
1.3 This standard does not purport to address all of the
temperatures may be used, when needed, to meet customer or
safety concerns, if any, associated with its use. It is the
vendor requirements, or both.
responsibility of the user of this standard to establish appro-
priate safety and health practices and determine the applica-
5.2 Prepare three “T-bend” test specimens in accordance
bility of regulatory limitations prior to use.
with Test Method D4145. The T-bend used should be agreed
upon between customer and vendor.
2. Referenced Documents
5.3 Examine the T-bend for cracking and tape pick-off in
2
2.1 ASTM Standards:
accordance with Test Method D4145 and record the results.
D4145 Test Method for Coating Flexibility of Prepainted
5.4 Place the formed test specimens in the 60 6 3°C (140 6
Sheet
5°F) oven for 16 h. Different times and temperatures may be
used if agreed upon between the customer and vendor.
3. Apparatus
5.5 Remove the test specimens and allow them to cool to
3.1 Gravity or Forced Air Laboratory Oven, capable of
room temperature.
maintaining a temperature of 60 6 3°C (140 6 5°F).
5.6 Repeat the tape adhesion test.
3.2 Bench Vise, with smooth jaws or inserts, 130 mm (5 in.)
permanently mounted on a work table or bench, or alternative
6. Report
equipment capable of making the appr
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation:D6491–99(Reapproved2003) Designation: D 6491 – 09
Standard Practice for
Evaluation of Aging Resistance of Prestressed Prepainted
1
Metal In a Dry Heat Test
This standard is issued under the fixed designation D 6491; 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 (´) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 This practice can be used to evaluate the resistance of a prestressed prepainted metal panel to cracking, or loss of adhesion,
or both, after accelerated heat aging. Most coil coated products are formed and bent into specific shapes to produce a final product.
These operations introduce stresses, which may be relieved by cracking of the coating after aging.
1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.
1.3 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.
2. Referenced Documents
2
2.1 ASTM Standards:
D 4145 Test Method for Coating Flexibility of Prepainted Sheet
3. Apparatus
3.1 Gravity or Forced Air Laboratory Oven, capable of maintaining a temperature of 60 6 3°C (140 6 5°F).
3.2 Bench Vise, with smooth jaws or inserts, 130 mm (5 in.) permanently mounted on a work table or bench, or alternative
equipment capable of making the appropriate bends.
3.3 Bending Dies or Test Shims , (optional).
3.4 10X magnifier, (optional).
3.5 Adhesive Tape.
4. Test Specimens
4.1 Cut samples 75 mm (3 in.) wide (across the bend direction) by whatever length is necessary to make the appropriate number
of bends. The direction of the bend may be transverse or longitudinal to the “rolling direction” of the metal—or as agreed upon
between customer and vendor.
5. Procedure
5.1Perform the fabrication at room temperature, 25 6 1°C (77 6 2°F). All test specimens should be equilibrated to the same
temperature before fabricating.
5.1 Perform the fabrication at room temperature, 25 6 1°C (77 6 2°F). All test specimens should be equilibrated to the same
temperature before fabricating. Different fabrication temperatures may be used, when needed, to meet customer or vendor
requirements, or both.
5.2 Prepare three “T-bend” test specimens in accordance with Test Method D 4145. The T-bend used should be agreed upon
between customer and vendor.
5.3 Exami
...