Page 1 Flammability Assurance for Printed Wiring Boards Certification by Similarity Analysis...
-
Upload
katherine-burham -
Category
Documents
-
view
215 -
download
1
Transcript of Page 1 Flammability Assurance for Printed Wiring Boards Certification by Similarity Analysis...
![Page 1: Page 1 Flammability Assurance for Printed Wiring Boards Certification by Similarity Analysis Proposal Boeing Commercial Airplanes Group PWB Material Working.](https://reader034.fdocuments.us/reader034/viewer/2022051614/55180de25503469b438b4690/html5/thumbnails/1.jpg)
Page 1
Flammability Assurance for Printed Wiring Boards
Certification by Similarity Analysis Proposal
Boeing Commercial Airplanes Group
PWB Material Working Group
June, 2003
![Page 2: Page 1 Flammability Assurance for Printed Wiring Boards Certification by Similarity Analysis Proposal Boeing Commercial Airplanes Group PWB Material Working.](https://reader034.fdocuments.us/reader034/viewer/2022051614/55180de25503469b438b4690/html5/thumbnails/2.jpg)
Page 2
• Test Results Summary• Background on PWB Working Group Task• Working Group/Test Plan Objectives• Test Results• Data Interpretation• Proposed Certification by Similarity Process• Recommendations
Agenda
![Page 3: Page 1 Flammability Assurance for Printed Wiring Boards Certification by Similarity Analysis Proposal Boeing Commercial Airplanes Group PWB Material Working.](https://reader034.fdocuments.us/reader034/viewer/2022051614/55180de25503469b438b4690/html5/thumbnails/3.jpg)
Page 3
Test Results Summary
• Data shows certification of PWBs by similarity is a valid process – Investigated IPC*-4101 /21 and /24 laminates, and IPC-CC-830 conformal
coatings meeting IPC-TM-650 or UL-94 V0 flammability requirements
• No factors showed significant effect on PWB FAR flammability – Laminate materials not a significant factor for /21 and /24 bare PWBs
• Thickness, layer count, PWB fabricator (fabrication process), and laminate manufacturer had minimal effect
– Adding conformal coating not a significant factor for /21 and /24 laminates
• Acrylic, urethane, and silicone conformal coatings all showed minimal effect on extinguishing time and burn length
• All conformal coated PWBs met FAR 25 requirements by large margin* The Institute for Interconnecting and Packaging Electronic Circuits
![Page 4: Page 1 Flammability Assurance for Printed Wiring Boards Certification by Similarity Analysis Proposal Boeing Commercial Airplanes Group PWB Material Working.](https://reader034.fdocuments.us/reader034/viewer/2022051614/55180de25503469b438b4690/html5/thumbnails/4.jpg)
Page 4
PWB Working Group – Project Background
• FAA IMFTWG Subgroup was established to evaluate flammability certification alternatives to FAR 12 second vertical flammability test for each PWB part number – Testing by individual part number is inefficient and expensive
– Baseline testing and establishing acceptable PWB industry specifications and process control provides better assurance
– Showing compliance by material similarity is a significant need
for aerospace electronics
• FAA Seattle Aircraft Certification Office is involved in process and test plan development
![Page 5: Page 1 Flammability Assurance for Printed Wiring Boards Certification by Similarity Analysis Proposal Boeing Commercial Airplanes Group PWB Material Working.](https://reader034.fdocuments.us/reader034/viewer/2022051614/55180de25503469b438b4690/html5/thumbnails/5.jpg)
Page 5
Flammability Test Plan Objectives
• Develop baseline FAR 25 flammability certification data for PWBs from IPC-4101 /21 and /24 resin “families” laminates and conformal coatings from IPC-CC-830 acrylic, urethane, and silicone material “families”
• PWB laminates meet IPC-4101 flammability requirements
• IPC-TM-650 (flammability) test method 2.3.10, or UL-94 V0
• Conformal coatings meet IPC-CC-830 plus UL-94 V0
• Validate that PWBs show similarity to previously tested materials contingent on meeting above criteria
![Page 6: Page 1 Flammability Assurance for Printed Wiring Boards Certification by Similarity Analysis Proposal Boeing Commercial Airplanes Group PWB Material Working.](https://reader034.fdocuments.us/reader034/viewer/2022051614/55180de25503469b438b4690/html5/thumbnails/6.jpg)
Page 6
Flammability Test Plan Objectives
• Classify and test PWBs according to IPC-4101 data sheets (resin types)– Test Plan Variables
• Test various thicknesses of PWBs from each resin system
• Test PWBs from several different pwb fabricators
• Test PWBs fabricated from different laminate manufactures
![Page 7: Page 1 Flammability Assurance for Printed Wiring Boards Certification by Similarity Analysis Proposal Boeing Commercial Airplanes Group PWB Material Working.](https://reader034.fdocuments.us/reader034/viewer/2022051614/55180de25503469b438b4690/html5/thumbnails/7.jpg)
Page 7
Flammability Test Plan Objectives
• Classify and test conformal coatings according to IPC-CC-830 material families
• Three types of conformal coatings were included• AR = Acrylic – Humiseal 1H71• UR = Urethane – Dymax 984 LVUF• SR = Silicone – Humiseal 1C53
• All coatings carry a UL-94 V0 flame rating
![Page 8: Page 1 Flammability Assurance for Printed Wiring Boards Certification by Similarity Analysis Proposal Boeing Commercial Airplanes Group PWB Material Working.](https://reader034.fdocuments.us/reader034/viewer/2022051614/55180de25503469b438b4690/html5/thumbnails/8.jpg)
Page 8
Test Summary
• 82 Production PWB’s tested – Full FAA Conformity appropriate for certification data
• PWBs fabricated from the two major IPC 4101 resin “families” used in PWB fabrication today– Low temp epoxy /21, high temp epoxy /24
• PWBs manufactured by four different PWB fabricators – Viasystems, Tyco, Holaday Circuits, Cosmotronics
• PWBs fabricated from IPC-4101 laminates from 4 different manufacturers – Nelco, Double Treat, Polyclad, Isola
• Both bare and conformal coated PWBs were tested– Acrylic, urethane, and silicone conformal coatings meeting IPC-CC-830
and UL-94 V0 – Acrylic, urethane, and silicone
![Page 9: Page 1 Flammability Assurance for Printed Wiring Boards Certification by Similarity Analysis Proposal Boeing Commercial Airplanes Group PWB Material Working.](https://reader034.fdocuments.us/reader034/viewer/2022051614/55180de25503469b438b4690/html5/thumbnails/9.jpg)
Page 9
Background on the Resin Systems
PWB Speci-fication Sheet #
Re-inforcement
Resin System ID Reference Glass Transition Range
Industry Flammability Testing
IPC-4101 /21
WOVEN E-GLASS FABRIC
Epoxy, Flame Resistant
NEMA FR-4, MIL-S-13949/04 – GF, GFN, GFK
110°C Minimum
IPC-TM-650 2.3.10 per IPC-4101---Monthly samples at the laminate level
lPC-4101 /24
WOVEN E-GLASS FABRIC
Majority Epoxy Modified or Unmodified, Flame Resistant
NEMA FR-4, MIL-S-13949/04
– GF, GFG
150°C - 200°C
IPC-TM-650 2.3.10 per IPC 4101 ---Monthly samples at the laminate level
![Page 10: Page 1 Flammability Assurance for Printed Wiring Boards Certification by Similarity Analysis Proposal Boeing Commercial Airplanes Group PWB Material Working.](https://reader034.fdocuments.us/reader034/viewer/2022051614/55180de25503469b438b4690/html5/thumbnails/10.jpg)
Page 10
Background on the three conformal coatings
Conformal Coat Description/Classification
Flammability Rating
Type AR (Acrylic) per IPC-CC-830Humiseal
UL-94 V0
Type UR (Urethane) per IPC-CC-830Dymax 984 LVUF
UL-94 V0
Type SR (Silicone) per IPC-CC-830Humiseal 1C53
UL-94 V0
![Page 11: Page 1 Flammability Assurance for Printed Wiring Boards Certification by Similarity Analysis Proposal Boeing Commercial Airplanes Group PWB Material Working.](https://reader034.fdocuments.us/reader034/viewer/2022051614/55180de25503469b438b4690/html5/thumbnails/11.jpg)
Page 11
Bare PWB Test ResultsBoeing Production P/N
PWB Fabricator IPC 4101 Data Sheet
Laminate Manufacturer
# of PWB Circuitry Layers
Thickness (inches)
Conformal Coating
Average Ext Time (seconds)
Average Burn Length (inches)
Meets Proposed Cert by Sim Criteria
906-30197 Viasystems 24 Isola 4 0.072 None 2.7 0.1 Yes906-71599 Viasystems 24 Isola 10 0.086 None 1.2 0.8 Yes906-40156 Viasystems 24 Isola 18 0.12 None 0 0 Yes
None 906-60424 Holaday 24 Double Treat 2 0.09 None 0 0.9 Yes906-30191 Holaday 24 Double Treat 6 0.09 None 0 0 Yes906-30193 Holaday 24 Double Treat 10 0.1 None 0 0.1 Yes
None 906-40055 Tyco 24 Nelco 12 0.062 None 0 0 Yes906-30263 Tyco 24 Nelco 14 0.079 None 2.4 0.1 Yes906-30264 Tyco 24 Nelco 14 0.091 None 0 0 Yes
None 906-40149 Cosmotronics 24 PolyClad 8 0.112 None 1.3 0.1 Yes906-60178 Cosmotronics 24 PolyClad 10 0.093 None 1.3 0.1 Yes906-71600 Cosmotronics 24 PolyClad 12 0.1 None 1.7 0.1 Yes
906-60242 Holaday 21 Double Treat 2 0.09 None 1.2 0.8 Yes906-30191 Holaday 21 Double Treat 6 0.09 None 0 0 Yes906-30193 Holaday 21 Double Treat 10 0.1 None 0 0.7 Yes
906-71600 * Cosmotronics 24 Polyclad 12 0.1 None 1 0.1 Yes
906-30193 * Holaday 24 Double Treat 10 0.1 None 0 0.05 Yes
906-40156 * Viasystems 24 Isola 18 0.12 None 0 0 Yes
*Testing Performed by FAA at FAA Tech Center
![Page 12: Page 1 Flammability Assurance for Printed Wiring Boards Certification by Similarity Analysis Proposal Boeing Commercial Airplanes Group PWB Material Working.](https://reader034.fdocuments.us/reader034/viewer/2022051614/55180de25503469b438b4690/html5/thumbnails/12.jpg)
Page 12
Conformally Coated PWB Test Results
Boeing Production P/N
PWB Fabricator IPC 4101 Data Sheet
Laminate Manufacturer
# of PWB Circuitry Layers
Thickness (inches)
Conformal Coating
Average Ext Time (seconds)
Average Burn
Length (inches)
Meets Proposed
Cert by Sim Criteria
906-30197 Viasystems 24 Isola 4 0.09 Acrylic 7.5 0.7 Yes906-71599 Viasystems 24 Isola 10 0.09 Urethane 1.1 0.4 Yes906-40156 Viasystems 24 Isola 18 0.1 Silicone 0 0.1 Yes
906-60242 Holaday 24 Double Treat 2 0.1 Acrylic 0.4 0.5 Yes906-30191 Holaday 24 Double Treat 6 0.09 Urethane 0 0 Yes906-30193 Holaday 24 Double Treat 10 0.1 Silicone 0 0.5 Yes
906-40055 Tyco 24 Nelco 12 0.062 Acrylic 0 0.5 Yes906-30263 Tyco 24 Nelco 14 0.079 Urethane 0 0 Yes906-30264 Tyco 24 Nelco 14 0.091 Silicone 0 0.2 Yes
906-40149 Cosmotronics 24 PolyClad 8 0.112 Acrylic 0 0.3 Yes906-60178 Cosmotronics 24 PolyClad 10 0.093 Urethane 0 0 Yes906-71600 Cosmotronics 24 PolyClad 12 0.1 Silicone 1.9 0.1 Yes
![Page 13: Page 1 Flammability Assurance for Printed Wiring Boards Certification by Similarity Analysis Proposal Boeing Commercial Airplanes Group PWB Material Working.](https://reader034.fdocuments.us/reader034/viewer/2022051614/55180de25503469b438b4690/html5/thumbnails/13.jpg)
Page 13
Burn Length Examples
![Page 14: Page 1 Flammability Assurance for Printed Wiring Boards Certification by Similarity Analysis Proposal Boeing Commercial Airplanes Group PWB Material Working.](https://reader034.fdocuments.us/reader034/viewer/2022051614/55180de25503469b438b4690/html5/thumbnails/14.jpg)
Page 14
Burn Length Examples
12 sec verticalZero” burn
length
12 sec vertical0.1” burn
length
60 sec vertical1” burn length
![Page 15: Page 1 Flammability Assurance for Printed Wiring Boards Certification by Similarity Analysis Proposal Boeing Commercial Airplanes Group PWB Material Working.](https://reader034.fdocuments.us/reader034/viewer/2022051614/55180de25503469b438b4690/html5/thumbnails/15.jpg)
Page 15
Test Results Summary
• Data shows certification of PWBs by similarity is a valid process – Investigated IPC*-4101 /21 and /24 laminates, and IPC-CC-830 conformal
coatings meeting IPC-TM-650 or UL-94 V0 flammability requirements
• No factors showed significant effect on PWB FAR flammability – Laminate materials not a significant factor for /21 and /24 bare PWBs
• Thickness, layer count, PWB fabricator (fabrication process), and laminate manufacturer had minimal effect
– Adding conformal coating not a significant factor for /21 and /24 laminates
• Acrylic, urethane, and silicone conformal coatings all showed minimal effect on extinguishing time and burn length
• All conformal coated PWBs met FAR 25 requirements by large margin* The Institute for Interconnecting and Packaging Electronic Circuits
![Page 16: Page 1 Flammability Assurance for Printed Wiring Boards Certification by Similarity Analysis Proposal Boeing Commercial Airplanes Group PWB Material Working.](https://reader034.fdocuments.us/reader034/viewer/2022051614/55180de25503469b438b4690/html5/thumbnails/16.jpg)
Page 16
Proposed Criteria for Flammability Certification of PWBs by Similarity
• FAR 25 flammability certification of Printed Wiring Boards PWBs by similarity to previously tested materials would be acceptable based upon the following processes and criteria:
– Industry specifications are used to group the PWBs into “material families”. Certification by similarity would be limited to materials with the following criteria;
1) PWBs claiming similarity must be manufactured in compliance with the same IPC-4101 laminate specification sheets (i.e. from the same resin family) for which FAR 25 certification data exists.
2) PWBs must be constructed only from laminates according to IPC-4101 specification sheets that either include a required IPC flammability test as a laminate test, or include the flammability test as a PWB drawing requirement test via UL 94 and carry a V0 flame rating.
3) Conformal coating used on the PWB must be IPC-CC-830 compliant and carry a UL-94 VO flame rating.
– PWB certification data is established per FAR (12-sec vertical). Another PWB part number may claim similarity to the original certification test data if the PWB satisfies the above criteria.
![Page 17: Page 1 Flammability Assurance for Printed Wiring Boards Certification by Similarity Analysis Proposal Boeing Commercial Airplanes Group PWB Material Working.](https://reader034.fdocuments.us/reader034/viewer/2022051614/55180de25503469b438b4690/html5/thumbnails/17.jpg)
Page 17
Proposed Certification by Similarity Process Flow
Conformalcoating registered
& tested UL 94 V0 ?
NO
YES
NO
FAR 25Flame Test
NO
YES
Flame Test Report
Design for a PWB
YES
PWB Laminates
registered & tested per IPC 4101* or
UL 94- V0?
Flammability Assured
Similarity to Documentedtest results
IsPWB
registered & tested per UL 94- V0?
**
* Requirement 2.10.3.1 IPC Test Method TM 650 for flammability
** Far 25 Certification data must exist for similar pwb constructed of similar laminate
![Page 18: Page 1 Flammability Assurance for Printed Wiring Boards Certification by Similarity Analysis Proposal Boeing Commercial Airplanes Group PWB Material Working.](https://reader034.fdocuments.us/reader034/viewer/2022051614/55180de25503469b438b4690/html5/thumbnails/18.jpg)
Page 18
Recommendations
• Short Term Recommendations– Formal Memo of Agreement between Boeing
and FAA to allow implementation of proposed PWB Certification by Similarity Process• Based upon released requirements document
• Mid/Long Range Recommendations– FAA IMFTWG PWB sub-group to document
PWB certification by similarity process for inclusion in appropriate FAA documentation (Fire Test Handbook, AC, ?)