1、 ENGINEERING MATERIAL SPECIFICATION Date Action Revisions Rev 03 2012 03 20 N Status No replacement named N. Benipal, NA 2006 03 22 Revised Inserted 3.0; Deleted 3.1, 3.2, 3.3, 3.16, 3.17, 4 1991 11 22 Released DF00E00107002091 L. Rumao Controlled document at www.MATS Copyright 2012, Ford Global Tec
2、hnologies, LLC Page 1 of 3 COATING, CONFORMAL, SILICONE OXIME CURE WSF-M99J378-A NOT TO BE USED FOR NEW DESIGN 1. SCOPE The material defined by this specification is a one component, primerless, moisture curing, solventless, silicone conformal coating. The material shall consist of silanol functiona
3、l methyl siloxane polymers, organofunctional silane crosslinker, organometallic catalysts, and adhesion promoters. A colored or UV fluorescent dye is optionally included as specified on the Engineering Drawing. 2. APPLICATION This specification was released originally for conformal coating used for
4、high reliability electronic assemblies. This coating is suitable for application by dip coating, brushing, or spray coating. 3. REQUIREMENTS Material specification requirements are to be used for initial qualification of materials. 3.0 STANDARD REQUIREMENTS FOR PRODUCTION MATERIALS Material supplier
5、s and part producers must conform to the Companys Standard Requirements For Production Materials (WSS-M99P1111-A). 3.4 APPEARANCE Translucent - Bulk Liquid Transparent - Cured Coating 3.5 VISCOSITY 240 - 400 mPa.s (ASTM D 1084, Brookfield model LVF, #2 spindle at 60 rpm) 3.6 NON-VOLATILE, min 90% (A
6、STM D 1644) 3.7 TENSILE STRENGTH, min 0.35 MPa (ASTM D 412) 3.8 ELONGATION, min 50% (ASTM D 412) 3.9 HARDNESS 15 - 35 (ASTM D 2240, Shore A scale) Note: Specimens for tensile, elongation, and hardness are to be cured as follows: . Cast slab samples a maximum thickness of 2 mm. . Use suitable non-sil
7、icone mold release to keep cured coating from sticking to mold. ENGINEERING MATERIAL SPECIFICATION WSF-M99J378-A Copyright 2012, Ford Global Technologies, LLC Page 2 of 3 . Allow samples to stand at 23 +/- 2 C and relative humidity 50% for 24 hours. . Stack slab samples to a minimum of 15 mm prior t
8、o measuring hardness. 3.10 ADHESION 3 B - 5 B (ASTM D 3359, Test Method B) Note: Specimens for adhesion are to be prepared as follows: . Dip ASTM D 709 grade FR-4 substrate into coating. Fixture and allow drain for 7 - 10 minutes. . Cure coating for 24 hours at 23 +/- C and 50 +/- 5% relative humidi
9、ty. Verify that coating is in the range of 0.05 - 0.13 mm. 3.11 DIELECTRIC STRENGTH 13.8 kV/mm (ASTM D 149) Note: Specimen to be 0.1 - 0.2 mm thick. 3.12 DIELECTRIC CONSTANT, max 3.5 (ASTM D 150, 10 MHz) 3.13 DISSIPATION FACTOR, max 0.020 (ASTM D 150, 10 MHz) 3.14 STABILITY Manufacturer shall certif
10、y that the material will meet specification requirements when stored for 3 months from date of shipment at a temperature not to exceed 27 C in the original sealed containers. 3.15 SILICONE VOLATILES, max 5% (FLTM AV 102-01) 5. GENERAL INFORMATION The information given below is provided for clarifica
11、tion and assistance in meeting the requirements of this specification. 5.1 HANDLING For production recirculating dip coating operations, it is necessary to provide a nitrogen or other inert gas blanket over the tank head space in order to avoid skinning and tank gelation. Drag-in of contaminants suc
12、h as tin and lead compounds from leave-on fluxes or other sources can affect tank stability and cure time of the coating. 5.2 STORAGE This coating cures as a result of reaction with atmospheric moisture. In order to prevent premature gelation and “skinning“ it is necessary to blanket partially fille
13、d containers and dip tanks with dry nitrogen. ENGINEERING MATERIAL SPECIFICATION WSF-M99J378-A Copyright 2012, Ford Global Technologies, LLC Page 3 of 3 5.3 COMPATIBILITY Compatibility of coating materials with substrates must be established prior to implementation. Organometallic compounds, which m
14、ay be found on some substrate surfaces, may affect cure and have the potential to reduce tank stability. The presence of surface contaminants, which are weakly adherent, can also contribute to adhesion failures under conditions of high humidity or cyclic temperature changes. 5.4 SURFACE PREPARATION
15、The coatings defined by this specification provide good wetting characteristics to a wide variety of materials. Silicone rubber films, however, have high moisture vapor permeability. It is important to insure that in cases where hydrolyzable or hygroscopic components or residues are to be coated, appropriate environmental testing (at representative or increased humidity levels) be performed.
