Evaluation and qualification of environmentally conscious manufacturing processes for commercial and military applications Page: 5 of 6
5 p.View a full description of this article.
Extracted Text
The following text was automatically extracted from the image on this page using optical character recognition software:
4
approval to use the process on several military projects. In
addition, it has sparked considerable interest from industry,
which resulted in a follow-on program (see Case Study 2).
Areas for future improvement included having additional
industry participants. The initial program was designed to
qualify the process for Motorola hardware applications; addi-
tional industry participants would have resulted in the new
process being qualified for more universal applications. More
formalized participation from the government soldering
community might have enhanced their probability of accep-
tance of the process for other applications; a custom test
vehicle with more performance-related features would have
qualified the process for more applications; and using addi-
tional soldering technologies, such as hand soldering, could
have contributed to qualifying a more "complete" solution.
Case Study 2- Low-Residue Soldering Task Force (LRSTF)
Considerable industry interest from the Motorola CRADA
program led Sandia and Texas Instruments (TI) to search out
additional industry and Government partners to participate in
a task force to study additional low-residue soldering proc-
esses and materials. Ten (10) different companies entered into
CRADAs with Sandia, including TI, Alliant Techsystems,
GM Hughes Electronics, Northern Telecom,' Teledyne
Electronic Technologies, North Bay Electronics, Andersen
Laboratory, Phoenix Microwave Corporation, M. S. Kennedy
Corporation and CTS Corporation. Eight (8) different
Government related organizations are participating with
Sandia on the program, including the Naval Air Warfare
Center (NAWC) at China Lake, NAWC-Indianapolis, US
Army-MICOM, US Air Force-Hanscom AFB, EMPF, EPA,
AlliedSignal/Kansas City Division (a DOE production plant)
and the National Defense Center for Environmental
Excellence.
The goals of the LRSTF program are to evaluate several
soldering technologies, including wave, hand and reflow sol-
dering; to verify these technologies for several product appli-
cations; to gather data to support Government approvals of
these new processes; and to transfer these technologies to
industry. The LRSTF was established with a diverse member-
ship that could facilitate incorporation of customer concerns
and requirements. In addition, input to the test program was
solicited from the tri-services, other government agencies,
and industry through mailings and open meetings. Initially, a
lengthy "shopping list" of possible requirements was devel-
oped, covering the following categories: circuit characteris-
tics, materials, circuit technology, soldering processes, flux
application techniques, testing and analysis. From this list, the
LRSTF established key components to form the basis of the
program test plan. Because satisfying all possible requests
would be nearly impossible, the task force aimed to meetapproximately 80% of the possible requirements on the list.
Several subsequent meetings and additional open review led
to development and finalization of the LRSTF program test
plan [2].
The requirements of the test plan were best met by a cus-
tom designed, fully functional PWB, to be soldered with three
different technologies: wave, reflow and hand soldering. This
program also used the IPC B-24 PWB and "Y" coupons for
test vehicles. The LRSTF PWB has four different functional
regions to simulate different product applications. These
regions included high speed digital circuitry, high-volt-
age/low-current circuitry, low-voltage/high-current circuitry,
and high frequency circuitry. The LRSTF PWB was fabri-
cated using both FR-4 and polyimide laminate materials.
The boards were assembled and soldered at four different
manufacturing sites: TI, Alliant Techsystems, GM Hughes
and AlliedSignal/KCD. The testing approach was similar to
the Motorola program, except the mechanical pull strength
and temperature cycling tests were deleted and a conformal
coating adhesion test was added. Testing was performed at
five sites: Sandia, EMPF, NAWC-China Lake, CSL Inc., and
AlliedSignal/KCD.
All manufacturing and testing for Phase 1 of this program
is complete. Although a few anomalies were noticed, they
appear non-process related. Initial program results were pre-
sented at a workshop in Albuquerque, on November 8 and 9,
1993, with nearly 200 people from industry and the
Government in attendance. The Phase 1 final report is sched-
uled for release in May 1995.
Positive results from this program mirror those of the
Motorola program, with the following improvements: 1) the
task force approach, with additional industry participants, has
been well received; 2) the more formal participation from
Government entities appears to have contributed to better
acceptance of the technologies; 3) the participation of an
independent assessor (Sandia) contributed to the acceptance
of the program and its results; 4) the use of a custom, multi-
function PWB enhanced the applicability of the program
results; and 5) the use of multiple soldering technologies
provides a more complete solution.
Additional observations from this program include: 1) it is
difficult to satisfy everyone's needs despite using a custom
test PWB; 2) it is very difficult to get military soldering
standards and specifications changed despite having data that
indicates process acceptability, coupled with overwhelming
industry support and that of many government soldering
technologists; and 3) more processing sites increases the need
for more "Murphy factor" allowances in program planning.
Upcoming Pages
Here’s what’s next.
Search Inside
This article can be searched. Note: Results may vary based on the legibility of text within the document.
Tools / Downloads
Get a copy of this page or view the extracted text.
Citing and Sharing
Basic information for referencing this web page. We also provide extended guidance on usage rights, references, copying or embedding.
Reference the current page of this Article.
Anderson, D. J.; Cranwell, R. M.; Iman, R. & Van Buren, P. D. Evaluation and qualification of environmentally conscious manufacturing processes for commercial and military applications, article, March 1, 1995; Albuquerque, New Mexico. (https://digital.library.unt.edu/ark:/67531/metadc1281281/m1/5/: accessed July 16, 2024), University of North Texas Libraries, UNT Digital Library, https://digital.library.unt.edu; crediting UNT Libraries Government Documents Department.