1、 WORLDWIDE ENGINEERING STANDARDS Material Specification GMW3008 Electrodeposition Primer - Generic Qualification Copyright 2013 General Motors Company All Rights Reserved July 2013 Page 1 of 14 1 Scope This specification details the general materials performance, compatibility, and processing inform
2、ation requirements for international company approval of electrodeposition (ELPO, E-Coat, electrocoat) primers. 1.1 Material Description. Materials qualified to this standard shall meet the performance requirements shown in Table A2. Additional testing and any exceptions to the requirements detailed
3、 herein are noted in the Appendix. Suppliers must demonstrate the technology as being production capable to reduce undue risk prior to release in a production facility. Any material development issues, such as chemical or performance values that fall outside of specified ranges, must be discussed wi
4、th the appropriate ELPO engineer for resolution. Material must successfully complete a production trial in a target facility prior to release for other facilities. Plant-specific tests must be performed after generic approval is received. An example of items evaluated in plant-specific testing inclu
5、des GM sealers and sealing compounds. 1.2 Symbols. Not applicable. 1.3 Typical Applications. This specification applies to medium, high-build and Hyper-throw materials for use on vehicles and space frames. These primers are intended to provide corrosion and chip resistance and may or may not be inte
6、nded for subsequent coating for appearance purposes. These coatings must perform over bare Cold Rolled Steel (CRS), Electrogalvanized (EG) coated steel, Hot Dip Galvanized coated steel (HDG), Galvannealed (Zinc-Iron Alloy (ZnFe) and Aluminum substrates (Al). 1.4 Remarks. Not applicable. 2 References
7、 Note: Only the latest approved standards are applicable unless otherwise specified. 2.1 External Standards/Specifications. ASTM D1475 ASTM D2369B ASTM D3960 ASTM D4399 2.2 GM Standards/Specifications. GM9618P GMW8 GMW14704 GMW16569 GM9626P GMW11 GMW14829 GMW16639 GM9632P GMW3041 GMW14872 GMW16656 G
8、M9633P GMW3059 GMW14873 GM9636P GMW8738 (I) GMW15282 GMW2 GMW14700 GMW15531 (I) (I) = This is a standard that is distributed only internally within General Motors. This standard cannot be distributed outside of General Motors. Contact the GM lead engineer for any instructions. 2.3 Additional Referen
9、ces. TMC003 Material Safety Data Sheet guidance documents (available at ). GM Paint Facility Process Specifications (available in Global Document Management (GDM). Surface Coatings Process Control Relationships Manual (available in GDM). 3 Requirements 3.1 Requirements on Delivery. Copyright General
10、 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 GMW3008 Copyright 2013 General Motors Company All Rights Reserved July 2013 Page 2 of 14 3.1.1 Chemical Requi
11、rements. 3.1.1.1 Volatile Organic Compounds (VOC) (ASTM D3960). The maximum allowable level of VOC is 72 g/L (0.6 L/gal), minus water. This test is to be run at 110 C, then repeated at 180 C for reference. 3.1.1.2 Chemical Fingerprint. GM may conduct infrared (IR) spectrophotometry analysis of the m
12、aterials supplied to this specification. Analysis may also be performed on ELPO that is removed from representative panels with film thickness and bake at target levels. The infrared spectra established for initial approval shall constitute a reference standard and shall be part of the submission pa
13、ckage. Formulation ranges for the various resin systems, pigments, flow control agents, additives (biocides, ultraviolet (UV) stabilizers), and key manufacturing control characteristics must be provided as part of the submission package. If a product change is proposed which is outside the technolog
14、y formulation limits, the responsible engineer must be notified. All ingredient ranges, key manufacturing control limits, and Certificate of Analysis ranges must pass standard gauge repeatability and reproducibility studies. 3.1.1.3 Delivery Documentation. The supplier shall be responsible for submi
15、tting a Certificate of Analysis with each batch of material arriving at a plant. This document shall be prepared and provide data as directed by each region. 3.1.2 Physical Requirements. 3.1.2.1 Product Information. The engineer responsible for technology qualification shall be contacted prior to te
16、st initiation. The following product information shall be submitted and include test results and typical ranges where applicable. For components: Volume solids (ASTM D2369B); Weight solids (Weigh/Bake/Weigh method), Density (ASTM D1475). Provide resin to paste-mixed product: Feed ratio and solution
17、conductivity (ASTM D4399). 3.1.3 Additional Requirements. 3.1.3.1 Submission Package. One (1) submission book and three (3) compact discs (CD) must be prepared for distribution. All test results, Key Product Characteristics (KPC), photographs and approval-related data are to be included as a permane
18、nt record of the initially approved material. 3.1.3.2 Mini-submissions. Some approvals will require mini-submissions when only minor changes are made to previously approved ELPO materials. Table A5 outlines testing requirements for a mini-submission. Tests may be added or deleted according to the na
19、ture and significance of the material modifications; these shall be determined prior to testing by the responsible engineer. 3.1.3.3 Panel Preparation. The specific number and substrate combinations to be evaluated are shown in Table A1. Test panels are to meet a profilometer Ra roughness of 25 in t
20、o 50 in. Initial test panel substrate roughness must be recorded prior to any coating applications. 3.1.3.4 Test Substrates. Table A2 outlines which substrate types are to be used and the durability requirements for each test. The required test panels must meet the designations in Table 1. Table 1:
21、Test Panel Designations Type Specification CRS GMW2-M-STS EG GMW11-M-STS HDG GMW8-M-STS ZnFe GMW8-M-STS Al AA611 Al AA6016 Note: AA Aluminum Company of America Other aluminum alloys may be requested for testing as new lightweight alloys are developed for production use. Copyright General Motors Comp
22、any Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW3008 Copyright 2013 General Motors Company All Rights Reserved July 2013 Page 3 of 14 3.1.3.5 Sample Size. Three (3) t
23、est panels are to be used for each test condition; however, the responsible engineer and the supplier may agree on a different number for specific tests prior to the initiation of generic approval work. All substrates, pre-treatments and coating layers shall be fully identified with source, product
24、code, batch number, bake description and film build. 3.1.3.6 Bake. The bake temperature and time ranges (minimum/maximum) and targets shall be recommended by the supplier and be provided on a time/temperature graph. All test panels shall be baked in indirect or electric ovens using a typical cure of
25、 165 C 5 C metal temperature for 15 minutes unless otherwise specified by the responsible engineer. Additional panels may be requested using a gas-fired oven for ELPO cure and subsequent evaluation. 3.1.3.7 Conditioning. When testing is to take place over fully layered panels, the samples shall be s
26、ubject to an aging period of at least 72 h at room temperature following the bake cycle. 3.1.3.8 Storage Requirements. The materials approved to this specification must be stable after storage under the following conditions: Resin: 180 days at +5 C to +35 C Paste: 90 days at +5 C to +35 C, as define
27、d by the ability to pass all initial test requirements in the application facility (i.e., assembly plant) 3.2 Processing Requirements. 3.2.1 Chemical Requirements. 3.2.1.1 Bath Performance. Performance requirements for the bath are outlined in Table A4. The system being tested shall be identical to
28、the intended production system and processing, when known. The bath should be evaluated both freshly prepared and following a 30% purge of ultrafiltrate that is replaced with deionized/reverse osmosis water. To determine bath stability, the following tests must be performed before and after 90 days
29、of agitation: pH, conductivity, percent solvent, percent solids and Pigment to Binder ratio (P/B). 3.2.1.2 Odor. Comparative odor testing is to be performed per GMW16639. This procedure examines the odor characteristics of emissions to the air from the process bath material. Equivalent or improved o
30、dor characteristics are required for new ELPO products. 3.2.1.3 pH. An operating bath shall be in the 5.2 pH to 6.2 pH range. Paste and resin pH shall be safe for storage tanks and plant personnel. 3.2.2 Mechanical Requirements. 3.2.2.1 Settling Test with Agitation. The dirt count on a horizontal pa
31、nel that has been subjected to the GM9633P procedure using test ELPO bath shall not exceed the count on the panel subjected to control bath. 3.2.2.2 Pump Shear Test. A pump shear test must be performed per GM9626P. The test duration must be a minimum of 16 h. The weight of a 200 mesh screen (plus re
32、siduals) is to be used to filter the test ELPO. The weight of any volatiles that precipitate during the test should not exceed the weight of an approved control. 3.2.3 Physical Requirements. 3.2.3.1 Appearance. The coating on samples shall be smooth, uniform, and free of sags, craters, or other surf
33、ace defects. The gloss shall be a minimum of 30, measured on a 20 gloss meter. 3.2.3.2 ELPO Film Smoothness. Profilometer Ra values on properly baked ELPO must achieve the following: Vertical surfaces: 14 in maximum Horizontal surfaces : 16 in maximum 3.2.3.3 ELPO Film Thickness. Interior and exteri
34、or ELPO film thickness requirements are outlined in Appendix B. 3.2.3.4 Throw Power. Throw power characteristics are to be assessed using a four (4)-panel box test. Panel faces A thru H must be evaluated and reported. Throw power must be equal to or better than the current production control but 9 m
35、 on the G face for traditional and Hyper-throw ELPO materials. The A face must 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 GMW3008 Copyr
36、ight 2013 General Motors Company All Rights Reserved July 2013 Page 4 of 14 target 17.5 m for traditional ELPO, and 15 m for Hyper-throw products. Box test details are shown in Appendix B. 3.2.3.5 Rupture Voltage; Pre-coated ZnFe Steel. Rupture characteristics must be evaluated and recorded at the f
37、ollowing voltages: Fresh material or non-purged - 150V, 200V, 250V, 275V, 300V, 325V, 350V, 375V and 400V at a bath temperature of 33 C (92 F), using a 5 s ramp time and a 60 s hold time. The test rating shall be based on profilometer and percent of panel ruptured and equivalent to or exceed that of
38、 the controls. Testing is to be performed per the ELPO suppliers panel coating protocol. 3.2.3.6 Edge Coverage. This testing is to be performed at the discretion of the responsible engineer. When required, test per GM9632P. Performance requirements are shown in Table A2. 3.2.3.7 Bake-off Loss. Test
39、per GM9636P. The amount of applied film that is lost as a result of the curing process must not exceed that of the control at an equivalent Pigment to Binder ratio. Target bake temperatures are to be used during this evaluation. 3.3 Performance Requirements. 3.3.1 Chemical Requirements. 3.3.1.1 Acce
40、lerated Corrosion Testing. GM laboratory cosmetic corrosion testing is required. All test cycles must achieve the equivalent of 5 years cosmetic corrosion exposure minimum. Creep is to be evaluated using GMW15282 (maximum peak to maximum peak). Lab testing is per GMW14872. 3.3.1.1.1 Road Test Option
41、s. Testing can be performed on test panels that are attached to the exterior of a vehicle on the road schedule or on full vehicles processed with the ELPO materials being qualified. The decision regarding panel or full vehicle testing shall be agreed upon by the responsible engineer and the supplier
42、 prior to initial testing. When required, a GMW8738 5-year road schedule is to be used for this option. 3.3.1.1.2 Full Durability Vehicle. Road testing can be performed at any global GM Corrosion Engineering proving ground approved to run GMW15531. A 5-year minimum equivalent road schedule per GMW87
43、38 is to be performed when required. 3.3.1.2 Lubricant Compatibility. Compatibility testing is to be performed per GMW16656. Reference oil RP-4107-S from Fuchs is to be used. 3.3.1.3 Fume Yellowing. The degree of topcoat yellowing resulting from the cathodic E-Coat, after baking, is to be determined
44、 per GM9618P. Use an electric or indirect-fired oven for this purpose. The resulting yellowing exhibited on the panel shall not exceed that of the control electrocoat. (Baseline data is to be acquired for quantitative comparison.) 3.3.1.4 Overbake and Underbake. The durability of overbaked and under
45、baked samples must be evaluated. All test samples are to be prepared per the requirements outlined in Table A3. Corrosion test per GMW14872, 5 years equivalent; Gravelometer test per GMW14700; Water immersion test per GMW14704. Tape adhesion testing is required per GMW14829 before and after water im
46、mersion. 3.3.1.5 Outdoor Exposure Testing. Prior to outdoor exposure testing, initial tape adhesion per GMW14829 must be performed. Outdoor exposure testing is required per GMW14873. Results are to be observed after six (6) months (visual only) and one (1) year of exposure. Evaluate corrosion creep
47、per GMW15282. The responsible engineer and supplier must agree upon the specific details of this requirement prior to the initiation of testing. 3.3.1.6 Bare and Oily Steel Performance. Corrosion testing is to be performed per GM14872 on panels prepared under the following conditions: Bare: Unphosph
48、ated panels must be prepared by wiping with acetone prior to ELPO coating. Oily: Panels must be prepared first by acetone wiping. Panels must then have Fuchs RP-4107-S lubricant applied at 3 g/m prior to ELPO coating. See Table A1 for requirements. 3.3.2 Mechanical Requirements. Not applicable. 3.3.
49、3 Physical Requirements. 3.3.3.1 Chip Resistance. Two (2) chip-resistance methods are to be performed. Low-temperature Method A or Method B is acceptable. Room-temperature testing per GMW14700 Method C is also required. The results must meet the specified requirements shown in Table A2 and be at least equivalent to the control. Room-Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for Resale
