ASTM D7893-13 - 1.11.2013
 
Significance and Use

5.1 Coil-coated metals are subjected to a wide range of environmental stresses. Corrosion at cut edges, damage points, and fabricated areas can occur and lead to premature failure. Proper preparation and rating of test panels produces meaningful test results that allows comparisons between metal substrates and their pretreatments as well as between coating systems.

5.2 Laboratory-prepared test panels give a relative comparison of the substrates and coating systems under test, but may not duplicate all of the stresses imposed on manufactured components. Validation of results on a manufactured product is recommended.

5.3 Laboratory accelerated corrosion testing is useful in evaluating relative performance of new and existing metal coatings, pretreatments, and paints. It is up to the participating parties to agree on the significance of these tests to actual use.

 
1. Scope

1.1 This guide has been written specifically for coil-coated metal building products.

1.2 This guide applies to preparation, testing, and rating of line-coated and laboratory-coated test panels for the purpose of comparing and ranking the panels for corrosion resistance and other related properties.

1.3 Testing may include accelerated laboratory corrosion tests and outdoor exposure tests.

1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

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.

 
2. Referenced Documents

D870-25

Standard Practice for Testing Water Resistance of Coatings Using Water Immersion

D5894-21

Standard Practice for Cyclic Salt Fog/UV Exposure of Painted Metal, (Alternating Exposures in a Fog/Dry Cabinet and a UV/Condensation Cabinet)

D5796-24

Standard Test Method for Measurement of Dry Film Thickness of Thin-Film Coil-Coated Systems by Destructive Means Using a Boring Device

D4585-07

Standard Practice for Testing Water Resistance of Coatings Using Controlled Condensation

D3359-23

Standard Test Methods for Rating Adhesion by Tape Test

D2803-09(2020)

Standard Guide for Testing Filiform Corrosion Resistance of Organic Coatings on Metal

D1654-24

Standard Test Method for Evaluation of Painted or Coated Specimens Subjected to Corrosive Environments

D610-25

Standard Practice for Evaluating Degree of Rusting on Painted Steel Surfaces

B117-26

Standard Practice for Operating Salt Spray (Fog) Apparatus

G85-19

Standard Practice for Modified Salt Spray (Fog) Testing

D2247-25

Standard Practice for Testing Water Resistance of Coatings in 100 % Relative Humidity

D4138-07a(2022)

Standard Practices for Measurement of Dry Film Thickness of Protective Coating Systems by Destructive, Cross-Sectioning Means (Includes all amendments and changes 7/1/2022).

G7-05

Standard Practice for Atmospheric Environmental Exposure Testing of Nonmetallic Materials

D7091-22

Standard Practice for Nondestructive Measurement of Dry Film Thickness of Nonmagnetic Coatings Applied to Ferrous Metals and Nonmagnetic, Nonconductive Coatings Applied to Non-Ferrous Metals

G169-01(2021)

Standard Guide for Application of Basic Statistical Methods to Weathering Tests

D1735-21

Standard Practice for Testing Water Resistance of Coatings Using Water Fog Apparatus

D714-25

Standard Test Method for Evaluating Degree of Blistering of Paints

J2334

Laboratory Cyclic Corrosion Test

G87-02(2023)

Standard Practice for Conducting Moist SO2 Tests