Abstract

These practices cover the different procedures employed in performing four types of treatments for the preparation of aluminum and aluminum alloy surfaces for painting. These processes are broadly classified into the following treatment types: solvent cleaning (Type A); chemical treatments (Type B); anodic treatments (Type C); and mechanical treatments (Type D). Service conditions shall dictate the type of surface preparation that should be employed, although the quality produced by any individual method may still vary with the type of alloy involved. Solvent cleaning does not disturb the natural oxide film on the metal and is applicable in ambient indoor or very mild service conditions. This treatment type may be performed by three methods, as follows: manual swabbing or dip washing; solvent spray cleaning; or vapor degreasing. Chemical treatments may be employed by the following eight methods: alkaline cleaners; sulfuric acid, chromium trioxide etch; alcoholic phosphoric acid cleaner; crystalline phosphate treatment; amorphous phosphate treatment; carbonate chromate treatment; amorphous chromate treatment; or 8) acid-bound resinous treatment. Anodic treatments will provide a protective inert oxide coating which increases corrosion resistance and promotes paint adhesion. This is recommended where maximum corrosion resistance by the treatment itself is desired, but should not be used on assemblies of dissimilar metals. This treatment type may be executed by two methods, namely: sulfuric acid anodic, or chromium trioxide anodic treatment. Mechanical treatments may be implemented by these two methods: hand or power wire brushing or other abrasive treatment; or sandblasting.

This abstract is a brief summary of the referenced standard. It is informational only and not an official part of the standard; the full text of the standard itself must be referred to for its use and application. ASTM does not give any warranty express or implied or make any representation that the contents of this abstract are accurate, complete or up to date.

1. Scope

1.1 These practices cover four types of treatment for preparation of aluminum and aluminum-alloy surfaces for painting, as follows:

1.1.1 Type A Solvent Cleaning.

1.1.2 Type B Chemical Treatments.

1.1.3 Type C Anodic Treatments.

1.1.4 Type D Mechanical Treatments. These four types cover a number of procedures, as described herein.

1.2 Variations in surface treatment produce end conditions which differ, and which do not necessarily yield identical results when paints are applied. Service conditions will dictate the type of surface preparation that should be selected, although the quality produced by any individual method may vary with different alloys.

1.3 This standard may involve hazardous materials, operations, and equipment. 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 (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.

ASTM Standards

D609 Practice for Preparation of Cold-Rolled Steel Panels for Testing Paint, Varnish, Conversion Coatings, and Related Coating Products

Military Standards

Federal Specification

Keywords

aluminum; pretreatment for painting; surface treatment; Aluminum; Aluminum alloys; Specimen preparation (for testing)--paints/related coatings ;

ICS Code

ICS Number Code 87.020 (Paint coating processes)

DOI: 10.1520/D1730-09

ASTM International is a member of CrossRef.

ASTM D1730