1、 ENGINEERING MATERIAL SPECIFICATION Date Action Revisions Rev 03 2015 02 10 N STATUS A2 Replace by WSS M7C79-B and A3 replaced by B2 U. Mueller, EU 2010 03 09 Revised Added -A3 version L. Rodrigues, FSA 1991 02 01 C01089481000 Released CD KS Copyright 2015, Ford Global Technologies, LLC Page 1 of 5
2、CAVITY WAX, SOLVENT BASED, 65% SOLIDS WSK-M7C79-A CAVITY WAX, HIGH SOLID, SOLVENT BASED, 85% SOLIDS WSK-M7C79-A2 CAVITY WAX, SOLVENT BASED, 40% SOLIDS WSK-M7C79-A3 NOT TO BE USED FOR NEW DESIGN 1. SCOPE The materials defined by these specifications are solvent based rust preventive compounds. 2. APP
3、LICATION These specifications were released originally for materials used as corrosion protective compound for automotive cavities. They form a soft, homogeneous film with good creapage and excellent corrosion protection. The material is applied to the vehicle after the paint process. 3. REQUIREMENT
4、S 3.0 STANDARD REQUIREMENTS FOR PRODUCTION MATERIALS Material suppliers and part producers must conform to the Companys Standard Requirements For Production Materials (WSS-M99P1111-A). 3.4 COMPOSITION Solvent based waxes and resins. 3.5 PHYSICAL PROPERTIES 3.5.1 Non Volatile Content (FLTM BI 102-01)
5、 WSK-M7C79-A, min 65% WSK-M7C79-A2, min 85% WSK-M7C79-A3, min 40% 3.5.2 Viscosity See Initial Sample A flow diagram to identify the characteristic properties of the material shall be added to the Initial Sample Report, together with a list of the relevant test parameter (temperature, shear rate, tim
6、e, etc.) and equipment details. 3.5.3 Density See Initial Sample (ASTM D 1475) +/- 0.05 g/mL ENGINEERING MATERIAL SPECIFICATION WSK-M7C79-A/A2/A3 Copyright 2015, Ford Global Technologies, LLC Page 2 of 5 3.5.4 Creeping Ability, min 20 mm (FLTM BJ 128-02) 3.5.5 Flow Rate See Initial Sample (FLTM BJ 1
7、28-01) +/- 5 mm The flow rate shall be determined at 20 C and at 40 C. 3.5.6 Color Beige or Amber 3.5.7 Appearance The wax shall dry to a smooth homogeneous film. 3.5.8 Storage Stability, min The storage stability must be adapted to the climate conditions at the individual plant. Min storage conditi
8、ons for all waxes: 6 months at 32 C and 6 months at 5 C Additionally for tropical climates: 3 months at 40 C After the storage, the material shall not show any insoluble separation or coagulation and must meet all specification requirements. 3.6 PREPARATION OF TEST PANELS The back side of test panel
9、s shall be protected to avoid excessive rusting during the following resistance tests. Panel edges, being subject of the investigation, must not be protected by any additional action. 3.6.1 Substrate (FLTM BJ 106-01, solvent wiped) 3.6.1.1 Ford Standard Steel Panels according to SAE J403 Steel or U-
10、MA 18006, if not otherwise specified. 3.6.1.2 Welded test assemblies per para 5.2. 3.6.2 Wax Application Prior to application, the wax must be stirred for 15 minutes. Test Panels: The wax may be sprayed airless or air assisted as recommended by the supplier to provide a homogenous film. Test Assembl
11、ies: An excess of wax shall be sprayed to the vertically positioned assemblies to enable the wax creeping into the welded joint. ENGINEERING MATERIAL SPECIFICATION WSK-M7C79-A/A2/A3 Copyright 2015, Ford Global Technologies, LLC Page 3 of 5 Two minutes after the wax application, the assemblies shall
12、be turned into a horizontal position for drying. 3.6.3 Application Temperature 20 25 C 3.6.4 Drying Time 5 minutes (23 +/- 2 C) 3.6.5 Dry Film Thickness on Test Panels 40 - 50 (FLTM BI 156-01 or gravimetrically) micrometer 3.7 REMOVAL The wax film must be removable from automotive topcoats at any ti
13、me without damaging the painted surface. The supplier must recommend a suitable solvent/cleaner process in the Initial Sample Report. Relevant topcoat systems are: Body enamel, catalyzed repair enamel, plastic paint, repair paint materials. 3.8 WATER DISPLACING PROPERTIES No rust Panel Preparation:
14、UMA 18001 test panels (may be cut to approximately a 5 x 7 cm size) shall be degreased and cleaned with an a applicable solvent. The panels shall not be touched after cleaning. Test Method: The test panels shall be completely immersed into an aqueous solution of NaCl (3%) for 2 minutes (complete wet
15、ting of the steel surface must be checked after the first 30 seconds). After draining in a vertical position for 10 seconds, the samples shall be immersed into the rust preventive under test for 2 minutes and then be dried vertically for 1 hour at room temperature. The test sample and an uncoated co
16、ntrol panel shall be exposed to the atmosphere above a saturated solution of sodium carbonate with an excess of solid sodium carbonate for 72 hours. Evaluation: No corrosion and no staining. 3.9 COMPATIBILITY The wax must be adaptable for application in accordance with the appropriate Ford Motor Com
17、pany Process Specification, e.g. U-C 800. The wax must be compatible with all related materials. 5. GENERAL INFORMATION The information given below is provided for clarification and assistance in meeting the requirements of these specifications. ENGINEERING MATERIAL SPECIFICATION WSK-M7C79-A/A2/A3 C
18、opyright 2015, Ford Global Technologies, LLC Page 4 of 5 5.1 MATERIAL REFERENCE All related materials used for approval of cavity wax according to this specification, e.g. substrate materials, paint materials, solvents, etc. as well as the application parameter shall be noted in the Initial Sample R
19、eport of the wax. 5.2 TEST ASSEMBLIES Test assemblies shall be prepared from U-MA 001-18001/6 Standard Panels according to the following sketch to simulate flanges, edges and joints of a vehicle body. ENGINEERING MATERIAL SPECIFICATION WSK-M7C79-A/A2/A3 Copyright 2015, Ford Global Technologies, LLC Page 5 of 5 1 o oSpot WeldingPointso o 200 mmo o100 mm 15 mm9015 mm 15 mm
