1、 ENGINEERING MATERIAL SPECIFICATION Material Name Specification Number Date Release No. Released 2014 06 11 N Status No replaced named L. Sinclair, NA 1994 07 29 NGA1E10370437007 Released R. Gordon K. Thurgood WP 3948-a Page 1 of 4 PRINTED CIRCUIT BOARDS, SOLDERABILITY WSF-M22P1-A1 NOT TO BE USED FO
2、R NEW DESIGN 1. SCOPE This specification defines the solderability requirements for printed circuit boards with a variety of solderable surface treatments. 2. APPLICATION This specification was released originally to define the solderability requirements of printed circuit boards with tin-lead solde
3、r coatings, anti-oxidant organic coatings and nickel-tin coatings over a copper base. 3. REQUIREMENTS 3.1 STATISTICAL PROCESS Suppliers must conform to the requirements of Ford Quality System Standard Q-101. A mutually acceptable Control Plan as described therein is required for material/source appr
4、oval. Appropriate statistical tools must be used to analyze process/product data so that variation in the final product is continuously reduced. 3.2 CONDITIONING AND TEST CONDITIONS All test values indicated herein are based on material conditioned in a controlled atmosphere of 23 +/- 2 C and 50 +/-
5、 5 % relative humidity for not less than 24 h prior to testing and tested under the same conditions unless otherwise specified. 3.3 SOLDERABILITY 3.3.1 As Manufactured Wave Solder Test Meets requirements (IPC-S-804, Method E) The flux applied for solderability testing shall be the same flux used in
6、the production soldering process for the circuit board under evaluation or an equivalent flux approved by the responsible Materials Engineering activity. See Section 5, GENERAL INFORMATION, for typical fluxes used within Ford Motor Company. ENGINEERING MATERIAL SPECIFICATION WSF-M22P1-A1 WP 3948-b P
7、age 2 of 4 Prior to solderability testing, circuit boards shall be steam aged and further conditioned per the following methods. The surface treatment class shall be specified on the drawing. If no surface treatment class is specified on the drawing, then Class 1 shall apply. Note: The supplier may
8、substitute IPC-S-804, Method A, Wave Edge Dip for Test Method E. Surface Treatment - Class 1 A. Hot Air Solder Leveled (HASL) B. Reflowed Tin/Lead C. Nickel/Tin D. Nickel/Gold Test Method: . 4 h of steam aging* . 2 minute bake at 200 +/- 5 C . 4 h aging at standard conditions (23 +/- 2 C and 50 +/-
9、5 % relative humidity). Surface Treatment - Class 2 A. Organic Coating intended for a single soldering operation. Test Method: . 1 h of steam aging* . 4 h aging at standard conditions (23 +/- 2 C and 50 +/- 5 % relative humidity). Surface Treatment, Class 3 A. Organic coating intended for multiple s
10、oldering operations. Test Method: . 1 h of steam aging* . 2 minute bake at 200 +/- 5 C . 4 h aging at standard conditions (23 +/- 2 C and 50 +/- 5 % relative humidity). ENGINEERING MATERIAL SPECIFICATION WSF-M22P1-A1 WP 3948-b Page 3 of 4 *Test samples to be suspended 40 mm over boiling distilled wa
11、ter in a nonmetallic container. The container shall be covered with a corrosion resistant stainless steel such that 80 - 90 % of the open area is covered. The test samples shall be suspended with a nonmetallic holder. 3.3.2 Circuit Boards in Storage Meets requirements Solderability testing shall be
12、done per 3.4.1 except the aging methods shall not include steam aging as shown below. Surface Treatment - Class 1 A. Hot Air Solder Leveled (HASL) B. Reflowed Tin/Lead C. Nickel/Tin D. Nickel/Gold Test Method: . 2 minute bake at 200 +/- 5 C . 4 h aging at standard conditions (23 +/- 2 C and 50 +/- 5
13、 % relative humidity Surface Treatment - Class 2 E. Organic coating intended for a single soldering operation. No test method required. Surface Treatment - Class 3 F. Organic coating intended for multiple soldering operations. Test Method: . 2 minute bake at 200 +/- 5 C . 4 h aging at standard condi
14、tions (23 +/- 2 C and 50 +/- 5 % relative humidity 3.4 SHELF LIFE When circuit boards are stored in their original cartons and packaging at a temperature no greater than 35 C and 85 % relative humidity, circuit boards with surface treatment Class 1 shall remain solderable for 6 months from the date
15、of manufacture, and circuit boards with surface treatment Class 2 or Class 3 shall remain solderable for 3 months after the date of manufacture. Solderability testing, after shipment from the sircuit board supplier, shall be checked per para 3.4.2. ENGINEERING MATERIAL SPECIFICATION WSF-M22P1-A1 WP
16、3948-b Page 4 of 4 3.5 SUPPLIERS RESPONSIBILITY All materials supplied to this specification must be equivalent in all characteristics to the material upon which approval was originally granted. Prior to making any change in the properties, composition, construction, color, processing or labeling of
17、 the material originally approved under this specification, whether or not such changes affect the materials ability to meet the specification requirements, the Supplier shall notify Purchasing, Toxicology and the affected Materials Engineering activity of the proposed changes and obtain the written
18、 approval of the Materials Engineering activity. Test data, test samples and a new code identification are to be submitted with the request. Substance restrictions imposed by law, regulations or Ford, apply to the materials addressed by this document. The restrictions are defined in Engineering Mate
19、rial Specification WSS-M99P9999-A1. 4. APPROVAL OF MATERIALS This specification is intended to define the performance and/or properties of finished parts or systems of combined materials. An Engineering Material Approved Source listing is not applicable for this specification. Product Engineering ma
20、terials referenced in this document and/or the affected engineering drawing, which require prior Engineering approval, are shown in the Engineering Material Approved Source List under the specification cited. 5. GENERAL INFORMATION The information below is provided for clarification and assistance i
21、n meeting the requirements of this specification. 5.1 COMMONLY USED FLUX SPECIFICATIONS 5.1.1 Adipic Acid/Isopropanol Solutions Ford Specifications: WSF-M13B49 WSF-M13B50 WSF-M13B51 5.1.2 No-Clean (Low to Medium Solids) Ford Specifications: TBD Supplier Product Designations: Koki JS-64MSS Best 4712 Best 4732
