1、Standard Specification for Inorganic Zinc-Rich Primer AASHTO Designation: M 300-03 (2012) American Association of State Highway and Transportation Officials 444 North Capitol Street N.W., Suite 249 Washington, D.C. 20001 TS-4c M 300-1 AASHTO Standard Specification for Inorganic Zinc-Rich Primer AASH
2、TO Designation: M 300-03 (2012) 1. SCOPE 1.1. This specification covers self-curing, inorganic zinc-rich primers for use on iron and steel surfaces. 1.2. Intended Use of the Primers: 1.2.1. Types I and II are intended for use on bridges, similar structural steel, and other ferrous metal surfaces sub
3、ject to corrosive atmospheric environments such as marine, industrial, and high humidity. 1.3. The values stated in SI units are to be regarded as the standard. 2. REFERENCED DOCUMENTS 2.1. Reference to standard specifications, testing procedures, and other standard procedures contained in this docu
4、ment shall be the latest edition of the published document at the date of this specification. 2.1.1. AASHTO Standard: Standard Specifications for Highway Bridges 2.1.2. ASTM Standards: A36/A36M, Standard Specification for Carbon Structural Steel B117, Standard Practice for Operating Salt Spray (Fog)
5、 Apparatus D185, Standard Test Methods for Coarse Particles in Pigments D512, Standard Test Methods for Chloride Ion In Water D520, Standard Specification for Zinc Dust Pigment D521, Standard Test Methods for Chemical Analysis of Zinc Dust (Metallic Zinc Powder) D562, Standard Test Method for Consis
6、tency of Paints Measuring Krebs Unit (KU) Viscosity Using a Stormer-Type Viscometer D610, Standard Practice for Evaluating Degree of Rusting on Painted Steel Surfaces D1475, Standard Test Method For Density of Liquid Coatings, Inks, and Related Products D1640, Standard Test Methods for Drying, Curin
7、g, or Film Formation of Organic Coatings at Room Temperature D1654, Standard Test Method for Evaluation of Painted or Coated Specimens Subjected to Corrosive Environments D1735, Standard Practice for Testing Water Resistance of Coatings Using Water Fog Apparatus D2247, Standard Practice for Testing
8、Water Resistance of Coatings in 100% Relative Humidity 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-4c M 300-2 AASHTO D2369, Standard Test Method for Volatile Content of Coatings D2371, Standard Te
9、st Method for Pigment Content of Solvent-Reducible Paints D3363, Standard Test Method for Film Hardness by Pencil Test D4417, Standard Test Methods for Field Measurement of Surface Profile of Blast Cleaned Steel D4541, Standard Test Method for Pull-Off Strength of Coatings Using Portable Adhesion Te
10、sters D4752, Standard Practice for Measuring MEK Resistance of Ethyl Silicate (Inorganic) Zinc-Rich Primers by Solvent Rub D4940, Standard Test Method for Conductimetric Analysis of Water Soluble Ionic Contamination of Blasting Abrasives D5894, Standard Practice for Cyclic Salt Fog/UV Exposure of Pa
11、inted Metal, (Alternating Exposures in a Fog/Dry Cabinet and a UV/Condensation Cabinet) D6580, Standard Test Method for the Determination of Metallic Zinc Content in Both Zinc Dust Pigment and in Cured Films of Zinc-Rich Coatings 2.1.3. Federal Standards: Fed. Std. No. 141, Paint, Varnish, Lacquer,
12、and Related Materials: Methods of Inspection, Sampling and Testing Fed. Std. No. 29, CFR 1910.1200 OSHA Hazard Communication Standard Fed. Std. No. 40, CFR, Part 59, Subpart D, Section 59.400 Through 59.413 National Volatile Organic Compound Emission Standards for Architectural Coatings 2.1.4. ANSI
13、Standard: American National Standards Institute (ANSI) B94.50, Style E 2.1.5. The Society for Protective Coatings (SSPC) Standards:1 AB 3, Abrasive Specification Number 3, Newly Manufactured or Re-Manufactured Steel Abrasive SP 5, White Metal Blast Cleaning 2.1.6. Other Document: Commercial Item Des
14、cription (CID) A-A-1689B; Tape, Pressure-Sensitive Adhesive, Plastic Film23. CLASSIFICATION 3.1. TypesInorganic zinc-rich primers covered by this specification shall be furnished in the following types, as specified in the invitation for bids, contract, or order. 3.1.1. Type IInorganic zinc-rich pri
15、mer solvent-base multiple components. 3.1.2. Type IIInorganic zinc-rich primer water-base multiple component system. 4. MATERIALS 4.1. The materials used in the manufacture of the primer shall conform to the requirements of the following specifications. 4.1.1. Zinc DustASTM D520, Type II 2015 by the
16、 American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-4c M 300-3 AASHTO 4.1.2. Vehicle shall be either a solvent solution or water solution of silicates, curing aids, tinting colors, suspension, and pot life control a
17、gents of the manufacturers choosing if no changes are made after initial approval of the primer. 4.1.3. The Volatile Organic Compound (VOC) content shall be stated by the manufacturer in accordance with Section 6.2. 4.1.4. PigmentThe pigment used in the formulation shall be basically zinc dust. Smal
18、l amounts of color and extender pigments may be used if the quantitative requirements of the complete paint are met. 5. REQUIREMENTS 5.1. ColorThe color of the inorganic zinc primer shall be as mutually agreed upon and such that a definite contrast between it and the color of blasted steel is readil
19、y apparent. 5.2. PigmentThe extracted pigment upon analysis shall conform to the minimum quantitative requirements specified in Table 1, and shall not vary more than a 2 percent or +3 percent metallic zinc content from the initially approved primer. 5.2.1. The x-ray diffraction pattern of the extrac
20、ted pigment shall be obtained for the initially approved primer. 5.3. Primer Quantitative RequirementsThe mixed primer shall meet the quantitative requirements specified in Table 1. Primer must meet applicable VOC content limitations for its intended use categories (shop or field application) as def
21、ined by Federal and local regulations. Primers for field coating shall comply with the requirements of 40 CFR, Part 59, Subpart D, Section 59.400 through 59.413. If thinning is necessary for application, the maximum amount of solvent added shall be such that the final product still complies with all
22、 the requirements of this section, including the VOC requirements. Table 1Requirements Characteristics Minimum Requirement Test Method Total solids, % by mass of paint 78 ASTM D2369 Pigment, % by mass of total solids 85 ASTM D2371 Metallic zinc, % by mass of pigment 85 ASTM D521 Metallic zinc, % by
23、mass of total solids 72 ASTM D6580 or ASTM D521 5.4. Physical PropertiesThe mixed primer shall meet the physical requirements of Table 2. Table 2Properties of Mixed Paint Characteristics Minimum Requirement Maximum Requirement Test Method Density, kg/m3(lb/gal) 2217 (18.5) ASTM D1475 Viscosity, KU 2
24、5C (77F) Manufacturers recommendation ASTM D562 Set to touch, minutes 25C (77F) wet film thickness of 75 to 100 m (3 to 4 mils) 30 ASTM D1640 Dry hard, h 25C (77F) wet film thickness of 75 to 100 m (3 to 4 mils) 24 ASTM D1640 Pot life 25C (77F), h 8 Section 5.5.4.1 2015 by the American Association o
25、f State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-4c M 300-4 AASHTO 5.5. Primer Qualitative RequirementsThe primer shall meet the following qualitative requirements. 5.5.1. MixingThe raw materials of the liquid portion of the inorganic
26、primer shall be mixed and dispersed as required to produce a product that is uniform, stable, free from grit, and conforms to the requirements of this specification. 5.5.2. The pigment portion of multicomponent paints, prior to mixing, shall be dry and loosely packed. After mixing, all types of coar
27、se particles and skins as residue retained on a standard 250-m (60-mesh) screen shall be no more than 0.5 percent by mass of total paint, regardless of type, in accordance with ASTM D185. 5.5.3. Storage LifeThe vehicle component shall not show thickening, curdling, gelling, gassing, or hard caking a
28、fter being stored unmixed for 9 months from date of manufacture in a tightly covered, unopened container at a temperature of 10 to 32C (50 to 90F). 5.5.4. Working PropertiesThe mixed paint shall spray easily, and shall show no streaking, running, sagging, or other objectionable features when tested
29、in accordance with Federal Standard No. 141, Methods 4331, and 4541. 5.5.4.1. Pot LifeAfter mixing, the pot life shall be determined by placing 350 to 400 mL of the mixed paint into a 500 mL (1 pt) double-friction, top-round paint can and sealing the lid. Place the sealed can into a water bath maint
30、ained at a temperature of 25C (77F). After 8 h the mixed paint shall not show curdling, gelling, gassing, hard caking, or a change in viscosity greater than 5 KU from the initial viscosity of the sample when determined in accordance with ASTM D562. 5.5.5. Test Panel PreparationSteel test panels (AST
31、M A36 hot-rolled steel, or equivalent), measuring 100 by 150 by 1.5 mm (4 by 6 by 1/16in.) unless otherwise designated shall be blast cleaned and coated with the zinc-rich primer. The panels shall be cleaned and coated on both sides and all edges. 5.5.5.1. The panels shall be cleaned in accordance w
32、ith SSPC-SP 5 using recyclable metallic abrasives in accordance with SSPC-AB 3. The abrasives shall have a maximum chloride content of 15 ppm determined in accordance with ASTM D512 and a maximum conductivity of 150 micromhos/cm determined in accordance with ASTM D4940. The abrasive mixture shall be
33、 approximately 60 percent SAE shot number S230 and 40 percent SAE grit number G40. Both the shot and grit shall have a Rockwell hardness of C45 3. The surface profile of the cleaned panels shall be 40 to 65 m (1.5 to 2.5 mils) when determined in accordance with ASTM D4417, Method C. The profile shal
34、l be clean, sharp, and free of embedded friable material, with adequate roughness to ensure effective adhesion of the primer. 5.5.5.2. The primer shall be applied to the cleaned test panels using airless spray equipment except when the paint manufacturers application information specifically states
35、only other methods of application are to be used. All primers shall be applied to panels mounted vertically at a distance of 530 mm (21 in.) from the tip of the spray gun. The equipment shall be capable of developing sufficient pressure to properly atomize the primer. The orifice size, application p
36、ressure, pump type and ratio, hose size and length, and any atypical application requirements shall be reported. If the pressure used varies by more than 10 percent from the suggested pressure listed in the manufacturers application data information, the actual pressure used and a statement explaini
37、ng the deviation shall be reported. 5.5.5.3. The dry film thickness shall be 65 to 90 m (2.5 to 3.5 mils) unless otherwise designated. Before any exposure tests, all panels shall be aged 14 days at 24 to 26C (75 to 79F) and 45 to 55 percent relative humidity. After aging of the test panels to be eva
38、luated for salt fog resistance, cyclic weathering resistance, bullet hole immersion, and humidity tests, the panels shall have the edges sealed and protected by applying vinyl tape around the outside edges. The vinyl tape shall extend 2015 by the American Association of State Highway and Transportat
39、ion Officials.All rights reserved. Duplication is a violation of applicable law.TS-4c M 300-5 AASHTO 5 mm (3/16in.) onto the coated surface from the edge of the panel. The vinyl tape shall be in accordance with CID A-A-1689B and have an approximate vinyl thickness of 110 m (4.3 mils) with an approxi
40、mate neoprene adhesive thickness of 25 m (1 mil). 5.5.5.4. The test panels for salt fog resistance and cyclic weathering resistance shall be scribed in accordance with ASTM D1654. The scribe shall be a single “X” centered on the test panel with rectangular dimensions of 50-mm (2-in.) top width and 1
41、00-mm (4-in.) height. To ensure proper positioning, cleanliness, and depth of the scribe, a template and a scribe-cutting tool shall be used. The scribe-cutting tool shall be a straight shank tungsten-carbide tip, lathe-cutting tool in accordance with ANSI B94.50, Style E. The operator shall bear do
42、wn hard and go over each arm of the scribe twice to ensure a clean scribe of sufficient depth to remove any zinc particles from the scribe and to expose clean steel. The exposed steel in the cut of the scribe shall be verified with a microscope. 5.5.6. MudcrackingThe coating, when applied in accorda
43、nce with Sections 5.5.5 through 5.5.5.3 to a 125- to 150-m (5- to 6-mil) dry film thickness, shall show no mudcracking that is visible to the unaided eye. 5.5.7. AdhesionThe coating, when applied and hardened in accordance with Sections 5.5.5 through 5.5.5.3, shall be tested for adhesion in accordan
44、ce with ASTM D4541, using apparatus under Appendix A4. The adhesive used to perform this test shall be a two-compound epoxy, containing no solvents (e.g., 100 percent solids). A minimum of four tests shall be performed on each panel. The average of the tests shall be a minimum pull-off adhesion valu
45、e of 2.4 MPa (350 psi). 5.5.8. Salt Fog ResistanceThis is an optional test, as determined by the purchaser. The coating, when applied, hardened, and scribed in accordance with Sections 5.5.5 through 5.5.5.4, shall pass 5000-h minimum exposure to salt fog (ASTM B117) without any blistering or rusting
46、 of the coated portion, with no undercutting from the scribe. (Slight rusting in the scribe mark will be permissible and resulting staining should be ignored.) Strips 6 mm (1/4in.) wide along the edges of the panel may be ignored. Testing shall be done in triplicate. 5.5.9. Cyclic Weathering Resista
47、nce TestSuitably sized panels shall be prepared in accordance with Sections 5.5.5 through 5.5.5.4 and tested in accordance with ASTM D5894, Cyclic Salt Fog/UV Exposure of Painted Metal, (Alternating Exposures in a Fog/Dry Cabinet). The coating shall pass fifteen 336-h cycles without any blistering o
48、r rusting of the coated portion, with no undercutting from the scribe. (Slight rusting in the scribe mark will be permissible and resulting staining should be ignored.) Strips 6-mm (1/4-in.) wide along the edges of the panel may be ignored. Testing shall be done in triplicate. 5.5.10. Bullet Hole Im
49、mersion TestThe coating shall be applied in accordance with Sections 5.5.5 through 5.5.5.3 at a dry film thickness of 75 to 90 m (3.0 to 3.5 mils) except for the panel size, which shall be 75 by 150 by 1.5 mm (3 by 6 by 1/16in.). A circular area of 38.1 mm (1.5 in.) in diameter, in the middle of each panel, shall be left uncoated. A small magnet may be used to hold a circular template in place for this purpose. Coat only the face of the panel with the primer bein
