1、 ENGINEERING MATERIAL SPECIFICATION Date Action Revisions 2016 07 05 N Status Replaced by WSS-M18P20-A1 B. Witkowski, NA 2005 03 09 Revised Revised referenced paragraph numbers throughout entire spec; replaced drawing in Figure 1; and deleted Figure 2 M. Mehandru 2004 05 27 Activated M. Mehandru Cop
2、yright 2016, Ford Global Technologies, LLC Page 1 of 7 SEALER, HEAT CURING, PAINTABLE WSS-M4G362-A2 NOT TO BE USED FOR NEW DESIGN 1. SCOPE The material defined by this specification is a heat curing paintable, non-tacky thermosetting sealer. 2. APPLICATION This specification was released originally
3、for material used to seal the roof ditch joint and provide a smooth surface for adhesively bonding a roof ditch molding. The material is applied on the sealer deck after vehicle electrocoat. The sealer is paintable and is suitable for use on non-visible exterior surfaces. The sealer has flow propert
4、ies providing a seal for the metal edge and any potential weld burn through. Note: Flow properties of this material may be adjusted depending on the application and plant conditions. The 45 flow must be specified on the engineering drawing. Material performance limits listed herein are representativ
5、e of the sealer released for the original application. 3. REQUIREMENTS 3.1 STANDARD REQUIREMENTS FOR PRODUCTION MATERIALS Material suppliers and part producers must conform to the Companys Standard Requirements For Production Materials (WSS-M99P1111-A). 3.2 DIMENSIONS As specified on engineering dra
6、wing and/or in Trim and Sealer manual 3.3 MATERIAL PROPERTIES 3.3.1 Solids, min 98% (ASTM D 2834, except heat at 102 +/- 3 C for 3 h in a mechanical convection oven) 3.3.2 Ash (based on solids weight) (ISO 3491, Method A, 760 +/- 30 C, reference para 4.2) The ash content tolerance for any one suppli
7、er shall be +/- 5% based on the recorded ash content for their originally approved production sample. 3.3.3 Specific Gravity (uncured material) (ASTM D 297, water displacement method: reference para 4.3) The specific gravity tolerance for any one supplier shall be +/- 0.1 based on the recorded speci
8、fic gravity of their originally approved production sample. ENGINEERING MATERIAL SPECIFICATION WSS-M4G362-A2 Copyright 2016, Ford Global Technologies, LLC Page 2 of 7 3.3.4 Shelf Life 90 Day Storage Stability at 23 +/- 2 C and 32 +/- 2 C. The supplier shall provide flow properties and cured adhesion
9、 data from initial through 90 days storage at 23 +/- 2 C and 32 +/- 2 C. Measurements shall be taken at monthly intervals. Data shall be made available to Materials Engineering prior to addition to the Approved Source List. Note: Heat greatly accelerates aging. Storage conditions for materials confo
10、rming to the requirements of this specification may vary depending on the individual product chemistry. In all cases, shelf life at 23 +/- 2 C shall be a min of 45 d. 3.4 MANUFACTURING PROPERTIES 3.4.1 Flow Properties Horizontal 45 2 - 7 mm * Test Method: Horizontal Panels - Apply a section of seale
11、r 150 x 25 +/- 0.1 to three 300 x 100 x 0.80 mm electrocoated steel panels per para 4.5. 45 Panel - Apply a 3.7 cm2 section of sealer to the center of three 300 x 100 x 0.80 mm electrocoated panels. Horizontal and 45 Test - Preheat the panels for 15 minutes at 110 +/- 2 C prior to sealer application
12、. This will heat stake the sealer to the panel. Allow the panels to cool at 23 +/- 2 C for 30 minutes. Scribe the original location of the samples prior to baking. Horizontal Panels - Bake the panels flat per the min bake schedule in para 4.4. Repeat this procedure for the max bake schedule. 45 Pane
13、ls - Bake the panels at a 45 orientation per the min bake schedule in para 4.4. Repeat this procedure for the max bake schedule. Remove panels from oven, cool, and measure material flow from original scribe. Save panels for para 3.5.3. *45 flow will be specified on the engineering drawing and on the
14、 part/material control plan. 3.4.2 Curl Test No curl allowed after 2 rebakes. Test Method: Apply a section of sealer 150 x 25 +/- 0.1 to three 300 x 100 x 0.80 mm electrocoated steel panels per para 4.5. Preheat the panels for 15 minutes at 110 +/- 2 C prior to sealer application. This will heat sta
15、ke the sealer to the panel. Allow the panels to cool at 23 +/- 2 C for 30 minutes. ENGINEERING MATERIAL SPECIFICATION WSS-M4G362-A2 Copyright 2016, Ford Global Technologies, LLC Page 3 of 7 Prepare test panels per matrix in Table 1, process number 2. Use current production paint as identified by the
16、 appropriate engineering office. Record any curling of the film after initial paint application. Using a razor blade, cut through the paint film at one side edge and the top edge of each sample. Subject the panel to an additional basecoat/clearcoat bake. Remove from oven and observe for evidence of
17、curling. Repeat this procedure once more for a total of 3 basecoat/clearcoat bakes. Report any evidence of curling and the paint system used. 3.4.3 Bridging, min 10 mm 3.4.3.1 Overlap Joint Test Method: Prepare two test fixtures as shown in Figure 1 using electrocoated panels prepared per para 4.5.
18、FIGURE 1 BRIDGING TEST FIXTURE PREPARATION 100 x 300 mm panel Zero gap 16mm gap Top View Side view of panel overlap with wedged gap SEALER TAPE (Center tape over panel edge) 50 x 300 mm panel (6mm edge bent up 90 degrees to stiffen panel) Spacer to control gap ENGINEERING MATERIAL SPECIFICATION WSS-
19、M4G362-A2 Copyright 2016, Ford Global Technologies, LLC Page 4 of 7 Apply a 1.8 mm thick and 18 mm wide ribbon of material to each test fixture. . Position ribbon such that it is centered over the panel edge. . Cure one test fixture at the min bake schedule per para 4.4. Subject the second test fixt
20、ure to the max bake schedule per para 4.4. . Allow test fixtures to cool for 1 h at 23 +/- 2 C. . Inspect test fixture and measure the maximum gap that material fails to bridges. Any evidence of tearing will constitute a failure. 3.5 ENGINEERING REQUIREMENTS 3.5.1 Adhesion Shall not be removed in a
21、continuous coherent film when subjected to the following environments. 3.5.1.1 Normal, 24 h at 23 +/- 2 C 3.5.1.2 10 APGE Cycles (FLTM BI 123-01) 3.5.1.3 Thermal Cycle . 4 h at 90 +/- 2 C . 4 h at 38 +/- 1 C and 95 - 100% relative humidity . 16 h at - 30 +/- 1 C . 4 h at 38 +/- 1 C and 95 - 100% rel
22、ative humidity . 4 h at 90 +/- 2 C . 16 h at - 30 +/- 1 C Sample preparation: SAE J1600, Method B, with the following modifications: . Apply a 75 x 200 mm strip of material along the center line of two electrocoated steel panels prepared per para 4.5. . Cure the material per bake schedules in para 4
23、.4. Report failure mode. 3.5.2 Low Temperature Resistance No cracking or (FLTM BV 101-02) loss of adhesion Place the panels prepared in para 3.4.1 in the slamming apparatus. Condition 4 h at - 40 +/- 1 C. The panel shall be slammed a total of 20 times. ENGINEERING MATERIAL SPECIFICATION WSS-M4G362-A
24、2 Copyright 2016, Ford Global Technologies, LLC Page 5 of 7 3.5.3 Compatibility with Production Paints - Initial Requirements No tackiness, staining, discoloration, dulling, softening, paint transfer, significant color shift, difference in orientation of metallic flakes (metallic paints) or other ob
25、jectionable appearance defects in the paint over the sealer. Note: Evidence of any defects as stated above shall be reviewed with Vehicle Operations and Materials Engineering. Test Method: . Prepare test panels per matrix in Table 1. Use current production paints as identified by Materials Engineeri
26、ng. (Panels shall be kept horizontal prior to baking, during the painting operation and during cure. Use gas fired oven for paint cure.) . Condition painted panels at 23 +/- 2 C for 4 - 24 h. . After 4 - 24 h at 23 +/- 2 C, perform the following tests on each panel: . Cross hatch adhesion check - FL
27、TM BI 106-01, Method B. . Resistance to Xylene - using a back and forth motion, rub surface of enamel 10 times with a small wad of cheesecloth which has been wetted with xylene. 3.5.4 Compatibility with Production Paints - Weathering Requirements No tackiness, staining, discoloration, chalking, glos
28、s change or other deleterious effects on topcoats when compared to paint not over sealer. Test Method: . Prepare test panels per matrix in Table 2. Use current production paints as identified by the Body Engineering Office. (Panels shall be kept horizontal prior to baking, during the painting operat
29、ion and during cure.) . Condition painted panels at 23 +/- 2 C for 72 h. . Subject panels for each paint/bake condition to each exposure listed below. Retain an unexposed panel as control. 3.5.4.1 Heat Age 14 d at 102 C 3.5.4.2 10 Thermal Cycles (as described in para 3.5.1.3) . After exposure, perfo
30、rm the following evaluation on each panel: . Cross hatch adhesion test per FLTM BI 106-01. . Examine test panels and compare to the control panel and to the paint not over sealer side of the panel for evidence of tackiness, staining, discoloration, gloss change, adhesion loss, or other deleterious e
31、ffects on top-coats. ENGINEERING MATERIAL SPECIFICATION WSS-M4G362-A2 Copyright 2016, Ford Global Technologies, LLC Page 6 of 7 3.6 QUALITY Material shall be a homogeneous product. It shall be consistent in color and texture, and free from objectionable odors during normal storage. It shall be suita
32、ble for the intended application. 3.7 FUNCTIONAL APPROVAL Materials being evaluated for approval to this specification shall be subjected to a production trial. Functional trial results must be approved by the affected assembly operation and Design Engineering. Results shall be made available to Mat
33、erials Engineering prior to material approval and release. 4. GENERAL INFORMATION The information given below is provided for clarification and assistance in meeting the requirements of this specification. 4.1 MECHANICAL CONVECTION OVEN The mechanical convection oven(s) used to cure the material sha
34、ll be capable of obtaining 205 C metal temperature on body steel (0.8 - 0.9 mm thickness) within 8 - 10 minutes. 4.2 ASH CONTENT, Typical 10% based on solids weight 4.3 SPECIFIC GRAVITY, Typical 1.15 4.4 BAKE SCHEDULES First Min Bake: 8 minutes at 135 +/- 1 C metal temperature (15 minutes total oven
35、 time max) Second Min Bake: 10 minutes at 135 +/- 1 C metal temperature (17 minutes total oven time max) Max Bake: 20 minutes at 155 +/- 1 C metal temperature (not less than 30 minutes total oven time) 4.5 SUBSTRATES Electrocoat primed steel panel 100 x 300 x 0.80 mm prepared per WSS-M2P180-A perfor
36、mance specification. Use current production paints as identified by Materials Engineering. 4.6 HARDNESS, Typical 50 - 60 (ASTM D 2240, Durometer D) 4.7 CURED TENSILE STRENGTH (without film), typical 2.0 - 5.0 MPa (ASTM D 412, Die C, pulled at 500 mm/minute. Cured at min bake schedules per para 4.4.
37、Tested at 23 +/- 2 C) 4.8 CURED ELONGATION (without film), typical 60 - 150% (Tested per para 4.7) ENGINEERING MATERIAL SPECIFICATION WSS-M4G362-A2 Copyright 2016, Ford Global Technologies, LLC Page 7 of 7 TABLE 1 - INITIAL PAINTABILITY MATRIX 1. Materials: Sealer, primer and topcoat as specified 2.
38、 Topcoat Colors: White, red, black and silver 3. Panel Preparation: See chart PANEL PREP SEALER GEL* PRIMER THICKNESS (MM) PRIME BAKE* (METAL TEMP) TOPCOAT THICKNESS (MM) - BC/CC TOPCOAT BAKE* (METAL TEMP) 1 No 0.005 0.03 135 C 8 min 0.025/0.05 141 C 10 min 2 Yes 0.005 0.03 163 C 8 min 0.025/0.05 14
39、1 C 10 min 3 No 0.005 0.03 163 C 8 min 0.025/0.05 141 C 10 min 4 No 0.005 0.03 177 C 8 min 0.025/0.05 141 C 10 min 5a No 0.005 0.03 163 C 8 min 0.025/0.05 141 C 10 min 6a No 0.005 0.03 163 C 8 min 0.025/0.05 141 C 10 min * Sealer gel prior to primer application - 5 minutes at 107 C metal temperature
40、. * Add 121 C for 10 minutes (oven time) ramp up prior top prime bake. * Min and max topcoat bakes may vary depending on the topcoat technology. A Two additional topcoat applications and bakes. B Three additional topcoat applications and bakes. 4. Panel Evaluation and Report: . Primer Appearance Bef
41、ore Topcoat 0 - Uniform good appearance 1 - Crawling/pin holes 2 - Crawling/pin holes and sags . Cross Hatch Adhesion Checks - FLTM BI 106-01 Method B (0.005 - 0.008, 0.013 - 0.018, and 0.023 - 0.03 mm primer film builds) 0 - 11% topcoat loss . Solvent Resistance Test After Topcoat - 10 Xylene Rubs
42、Record the number of rubs to paint transfer (avoid rubbing over sharp corners and edges) TABLE 2 - WEATHERABILITY PAINT MATRIX 1. Materials: Sealer, primer and topcoat as specified (include current materials during test for comparison) 2. Topcoat Colors: White and silver 3. Panel Preparation: See ch
43、art PANEL PREP SEALER GEL* PRIMER THICKNESS (MM) PRIME BAKE* (METAL TEMP) TOPCOAT THICKNESS (MM) - BC/CC TOPCOAT BAKE* (METAL TEMP) 1 No 0.013 135 C 8 min 0.013/0.25 141 C 10 min 2 Yes 0.013 163 C 8 min 0.025/0.05 141 C 10 min * Not required for weathering evaluations. * Add 107 C for 10 minutes (oven time) ramp up prior to prime bake. * A higher topcoat bake can be used if recurs may vary depending on the topcoat technology.
