1、 WORLDWIDE ENGINEERING STANDARDS General Specification GMW14669 Organic Coating Performance for Exterior and Interior Metallic Components Copyright 2013 General Motors Company All Rights Reserved January 2013 Originating Department: North American Engineering Standards Page 1 of 9 1 Introduction Not
2、e: Nothing in this standard supercedes applicable laws and regulations. Note: In the event of conflict between the English and domestic language, the English language shall take precedence. 1.1 Scope. This performance standard applies to organic surface finishes on metallic automobile body parts and
3、 components. 1.2 Mission/Theme. This standard covers the performance requirements for applied organic surface finishes on metallic automobile body parts and components. The focus is the performance of coated parts for which the coating is GM approved (as evidenced by its presence in MATSPC or other
4、regional approved material database.) However, approval criteria are included for instances when new material is necessary. Six (6) types of requirements are specified in Section 1.3, dependent upon the severity of service operation of the component. All interior painted metal parts must also meet t
5、he requirements of GMW14444. 1.3 Classification. 1.3.1 Type A1. Applicable to surface finishes used on the external body and on external components in areas of exceptionally severe service, e.g., vehicle front, sides, and roof. 1.3.2 Type A2. Applicable to surface finishes used on the external body
6、and on external components in areas of severe service operations, e.g., vehicle rear-facing areas with little/no chipping exposure. 1.3.3 Type A3. Applicable to surface finishes used on external components which are not Type A1 or Type A2, and for which performance requirements must be specially def
7、ined; this type typically is not used. 1.3.4 Type B1. Applicable to surface finishes used on internal body parts and components in areas of exceptionally severe service operations, e.g., solar direct sunlight exposure, and corrosion items in contact with wet floor, such as lower seat structure. 1.3.
8、5 Type B2. Applicable to surface finishes used on internal body parts and components in areas of severe or moderate service operation, e.g., solar indirect sunlight exposure, and corrosion items readily visible near floor, such as brake pedal arm, speaker grilles in lower door. 1.3.6 Type B3. Applic
9、able to surface finishes used on internal components in areas of normal service operation, e.g., solar no direct sunlight exposure; corrosion any other steel components visible with difficulty, such as upper structure under seats, structures visible with closures (e.g., glove box) open or seats fold
10、ed. Note: Structures not visible to customers (e.g., instrument panel support) may require only temporary corrosion protection not covered under this standard. 1.3.7 It is anticipated that some interior components may have mixed service severity (e.g., B1 for corrosion and B3 for solar). In this cas
11、e, the most severe type shall be listed and exception(s) noted on the engineering drawing. 1.3.8 This standard does not cover performance requirements for: 1.3.8.1 Organic coatings on highly stressed exterior parts (e.g., road wheels). See GMW14670 for steel wheels and/or GMW14885 for aluminum wheel
12、s. 1.3.8.2 Organic coatings on chassis components. See GMW14671. 1.3.8.3 Organic coatings on plastic parts. See GMW14797. 1.3.8.4 Organic coatings on fasteners, unless not covered by other specification. 2 References Note: Only the latest approved standards are applicable unless otherwise specified.
13、 Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW14669 Copyright 2013 General Motors Company All Rights Reserved January 2013 Page 2 of 9
14、 2.1 External Standards/Specifications. ISO 105-A02 SAE J1545 ISO 2813 SAE J1767 ISO 15184 SAE J2527 2.2 GM Standards/Specifications. GMW3005 GMW14701 GMW3059 GMW14729 GMW3208 GMW14797 GMW3286 GMW14829 GMW3417 GMW14865 GMW14124 GMW14872 GMW14162 GMW14885 GMW14333 GMW15282 GMW14334 GMW15287 GMW14444
15、GMW15356 GMW14670 GMW15357 GMW14671 GMW15359 GMW14698 GMW15891 GMW14700 2.3 Additional References. None. 3 Test Preparation and Evaluation 3.1 Resources. 3.1.1 Calibration. The test facilities and equipment shall be in good working order and shall have a valid calibration label. 3.1.2 Alternatives.
16、Alternative test facilities and equipment may also be used. However, all measuring variables as specified in this standard shall be determined correctly with respect to their physical definition. 3.1.3 Facilities. Apparatus as required by the appropriate test methods. 3.1.4 Equipment. Not applicable
17、. 3.1.5 Test Vehicle/Test Piece. The size, dimensions and number of test pieces shall be as specified in the relevant test method for the property concerned. Unless otherwise specified, three (3) samples per test shall be run. 3.1.6 Test Time. Not applicable. 3.1.7 Test Required Information. Not app
18、licable. 3.1.8 Personnel/Skills. Not applicable. 3.2 Preparation. Conditioning, where required, shall be as specified in the relevant test method for the property concerned. 3.3 Conditions. 3.3.1 Environmental Conditions. Not applicable. 3.3.2 Test Conditions. Deviations from the requirements of thi
19、s standard shall have been agreed upon. Such requirements shall be specified on component drawings, test certificates, reports, etc. 3.4 Instructions. Not applicable. 3.5 Data. Not applicable. 3.6 Safety. This standard may involve hazardous materials, operations, and equipment. This standard does no
20、t propose to address all the safety problems 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. 3.7 Documentation. Samples of components or materia
21、l released to this standard shall be tested for conformity with the requirements of this standard and approved by the responsible GM Department prior to the start of delivery of production level components or materials. Any change to the component or material, e.g., design, function, properties, man
22、ufacturing process and/or location of manufacture requires a new release of the product. It is the sole responsibility of the supplier to provide the customer, unsolicited, with documentation of any change or modification to the product/process, and to apply for a new release. If not otherwise agree
23、d to, the entire verification test shall be repeated and documented by the supplier prior to start of delivery of the modified or changed product. In some cases, a shorter test can be agreed to between the responsible GM department and the supplier. 3.7.1 Test Results. The results shall be represent
24、ed in a test report with reference to this standard. 4 Requirements and Procedure 4.1 General. A general summary of requirements is shown in Table A1. 4.1.1 As per GMW3059 requirements, all coatings, pretreatments, post treatments, adhesion promoters, etc., shall be free of hexavalent chromium (Chro
25、me VI). 4.2 Crosshatch Adhesion Test. Test per GMW14829, Method A. Coatings must perform both as-received and after humidity exposure to GMW14729 of the hours shown. Types A1 and A2 Requirement: Rating 0 after 120 h humidity. Copyright General Motors Company Provided by IHS under license with Genera
26、l Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW14669 Copyright 2013 General Motors Company All Rights Reserved January 2013 Page 3 of 9 Type A3 Requirement: Must be specially defined. Type B1 Requirement: Ratin
27、g 0 or 1 after 96 h. Types B2 and B3 Requirement: Rating 0 or 1 after 24 h. 4.3 Testing to High-humidity Environments. Test per GMW14729. Types A1 and A2: 240 h. Type A3: Must be specially defined. Type B1: 96 h. Types B2 and B3: 72 h. Requirement: No surface change. 4.4 Corrosion Tests. The determi
28、nation of the resistance of the organic coating to corrosion has to be done by a Cyclic Corrosion Test. If the coating is intended to be used for painting of aluminum substrates, an additional Cyclic Climate Test is necessary (refer to paragraph 4.4.3). Body assembly or subassembly parts and compone
29、nts shall be tested in vehicle position. Interior components/assemblies shall have coverings (e.g., seat cushions) removed. 4.4.1 Salt Spray Fog Test. Note: When required by GM Materials Engineering, the Salt Spray Fog Test may be used for bare steel or aluminum substrates as part of a development p
30、rogram or for rapid quality testing once correlation to cyclic corrosion performance is established. Salt spray fog testing for 336 h (Types A1 and A2), 168 h (Type B1), 96 h (Type B2), and 24 h (Type B3) shall be performed according to GMW3286 requirements. No corrosion (except along scribe lines)
31、blisters or any change of surface allowed. Total scribe creepback determined per GMW15282 shall be 3 mm maximum for all substrates. The evaluation of scribe creepback can be determined by scrape and blow-off with compressed air per GMW15282, by using tape adhesion per GMW14829, or by using oblique l
32、ighting to highlight the edge of creepback/blister areas. Note: Slight rust at edges is permitted for Type B (non-visible parts only) but shall not exceed 20% of the length of exposed edges unless otherwise noted in specific part information. 4.4.2 Cyclic Corrosion Test. A Cyclic Corrosion Test per
33、GMW14872 is required to be performed on normally processed parts or representative sections of parts. Refer to Table A2 for specific details associated with required test duration for specified test class suffix, vehicle area, and mounting location. Type A Requirement: Corrosion rating of 9 or bette
34、r per GMW15356, GMW15357 or GMW15359. Type B Requirement: Corrosion rating of 10 per GMW15356, GMW15357 or GMW15359. 4.4.3 Climate Tests for Painted Parts with Aluminum Substrates. Required for Types A1, A2, and B1. Aluminum substrates must be tested and evaluated via the Filiform Corrosion Test. If
35、 required by drawing note, product Statement of Requirements, Material Specification Sheet, etc., the Cyclic Climate Test must be performed additionally. 4.4.3.1 Cyclic Climate Test (For Aluminum Substrates Only). The determination of resistance of the coating to corrosion under cyclic alternating c
36、onditions has to be performed according to GMW14124, Cycle U, for ten (10) total cycles (10 weeks) or per an acceptable method on agreement of the supplier and GM Materials Engineer. After the test, no corrosion or blisters except along the scribe line, or any change of surface is allowed. Total cor
37、rosion creepback measured per GMW15282 shall be 2 mm maximum. (The evaluation of scribe creepback can be determined by scrape and blow-off with compressed air per GMW15282, by using tape adhesion per GMW14829 or by using oblique lighting to highlight the edge of creepback/blister areas.) 4.4.3.2 Fil
38、iform Corrosion Test (For Aluminum Substrates Only). Test parts per GMW15287. Painted parts must meet a filiform resistance requirement of no more than 4 mm maximum length of any filament from the scribe line after a period of 672 h in humidity. Also, there shall be no filament growth on the non-scr
39、ibed test surfaces at the end of the test, excluding sample-prepared cut edges. 4.5 Scratch Resistance. Following GMW3286 salt spray, test per GMW14698, Method A (with Test Tip 2) or Method B. Performance requirement is no penetration of the test coating layer at 4 N load. 4.5.1 Optionally, pencil h
40、ardness test per ISO 15184 may be used to evaluate scratch resistance; the requirement is 1 H to 3 H. 4.6 Cure Test. Test per GMW15891. This is applicable to all coating types. Samples shall show no more than slight, barely observable, change to the paint surface (Rating 0 or 1). Copyright General M
41、otors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW14669 Copyright 2013 General Motors Company All Rights Reserved January 2013 Page 4 of 9 4.7 Resistance to S
42、urface Deterioration by Chemical Action. Test per GMW14701. Types A1 and A2 Requirement: Rating 8 or better. Type A3 Requirement: Must be specially defined. Types B1, B2 and B3 Requirement: Not applicable. 4.8 Fuel Resistance. Test per GMW14333 - A. This test shall be run on all parts which may be c
43、ontacted by fuel and/or if specifically required by drawing notes. 4.9 Resistance to Cleaning Agents. Test per GMW14334, using agents appropriate for interior or exterior paints. This testing does not apply to paint Types A3 or B3 unless specifically defined on the drawing. GMW14334, Code B, pertain
44、s to Types A1 and A2; Codes A and C pertain to coating Types B1 and B2. Requirement for All Types: Rating 2. Note: Must choose cleaning compounds appropriate for and available in vehicle operating areas. 4.10 Resistance to Stone Impact. Test per GMW14700, Method A or B, and Method C. Type A1 Require
45、ment: Rating 8. Type A2 Requirement: Rating 7. Type A3 Requirement: Must be specially defined. Type B Requirement: Not applicable. 4.11 Wear Resistance. The surface finish (topcoat) on painted metal substrates shall show no wear-through or other adverse effects after 1000 cycles per nominal 25 (40 c
46、ycles per micron of wear) micrometer dry film build of the Taber abrader wear tester per GMW3208, CS-10 wheels, with a 500 g load. This is applicable to Type B coatings only; Type A coatings will demonstrate car wash scratch resistance per GMW3005 criteria (test sample vs. control sample using GMW14
47、865). 4.12 Gloss. Test per ISO 2813. Gloss standards and measurement frequency are specified elsewhere in other documents by a GM Engineering unit. 4.13 Weather Resistance. Paragraphs 4.13.1 and 4.13.2 apply only to topcoat systems and for initial (paint) sample approval only. Note: These requiremen
48、ts apply to interior (Type B) parts only. Exterior (Type A) paint and part requirements are covered in GMW3005, Class 2, Type B or C. Note: These requirements are not intended for use in routine quality testing. Deviation from the stated requirements is subject to arbitration between the supplier an
49、d the appropriate GM Materials Engineer. 4.13.1 Natural Weathering. Natural weathering is required for the validation process of a paint material itself. This test is not applicable for painted body parts. Refer to Table B1 for specific regional requirements and test methodologies. 4.13.2 Accelerated Weathering. If a supplier shall be able to prove a positive result of two (2) years natural weathering test, the accelerated weathering test is not applic
