Orlando, FL:  A joint test conducted by researchers of the U.S. Air Force Research Laboratory, Oak Ridge National Laboratory, Ball Aerospace & Technologies Corporation, Brigham Young University, U.S. Army RDECOM-ARDEC, and nScrypt, Inc.’s research arm, Sciperio, used two types of 3D printing technology to compare the mechanical and thermal resilience of different materials for printing electronics for harsh conditions.  The paper describing the test is available here.

The two 3D printing technologies used by the team were an nScrypt Factory in a Tool (FiT) platform outfitted with a SmartPump^TM microdispensing tool head and a powder bed fusion laser projection technology developed by the University of South Florida called Large Area Projection Sintering (LAPS).

Using the two technologies, the team printed a simple electronic device with a conductive trace and hollow cylinder representative of printed electronics packaging that would survive harsh environmental conditions.   The nScrypt system was the primary manufacturing system and the LAPS system manufactured a subset of samples for comparison.

The tests followed Military Standard (MIL STD) 883 K and included resiliency evaluation for die shear strength, temperature cycling, thermal shock, and high G loading by mechanical shock.  The project assessed the ability of printed electronic multi-material systems to meet harsh environmental conditions typical of qualification requirements in traditional electronics packaging.

The electronic device consisted of a cured conductive paste circuit (DuPont CB028) on a substrate and a packaging cylinder without a cap.  The nScrypt SmartPump^TM was used to microdispense both the CB028 for the conductive circuit and Master Bond (MB) SUP10HTND epoxy for the packaging cylinders.  A subset of packaging cylinders was sintered with Nylon 12 using LAPS. 

The team chose Kapton® and FR4 as substrate materials because they are both commonly used in the electronics industry and provide a flexible and rigid substrate, respectively.

Results indicated that DW Master Bond epoxy devices made with the nScrypt FiT show resilience to extreme temperatures, thermal shock, and mechanical shocks while also surpassing the die shear strength failure criteria specified by the military standard.  The LAPS sintered Nylon devices also showed mechanical resilience to thermal shock and surpassed the die shear strength failure criteria. However, there were some open circuits, increases in resistance, and delamination when LAPS Nylon devices were subjected to extreme temperatures and 20,000 G shock loading normal to the substrate.

The team was comprised of Clayton Neff, U.S. Air Force Research Laboratory, Fuzes Branch, Munitions Directorate, Eglin AFB; Justin Nussbaum, Oak Ridge National Laboratory; Chris Gardiner, Ball Aerospace and Technologies Corporation; Nathan B. Crane, Brigham Young University, Department of Mechanical Engineering; James L. Zunino, U.S. Army RDECOM-ARDEC Picatinny Arsenal; and Mike Newton, Sciperio, Inc. (nScrypt’s research arm), Orlando, FL.

Table 1 Coefficient of thermal expansion (CTE) for materials studied

Fig. 1: CB028 circuits and dies: (a) MB on Kapton®, (b) MB on FR4, and (c) LAPS Nylon 12 on FR4. Note the conductive strip is highlighted in the middle of the cup that connects the circuit underneath the cup.

About nScrypt

Orlando, Florida-based nScrypt designs and manufactures award-winning, next-generation, high-precision microdispensing and 3D Manufacturing equipment and solutions for industrial applications, with unmatched accuracy and flexibility. Serving the printed electronics, electronics packaging, solar cell metallization, communications, printed antenna, life science, chemical/pharmaceutical, defense, space, and 3D printing industries, our equipment and solutions are widely used by the military, academic and research institutes, government agencies and national labs, and private companies. The nScrypt BAT Series Bioprinter, which won the 2003 R&D 100 award, launched to the International Space Station in July 2019. www.nScrypt.com.  

About Sciperio

Sciperio challenges the boundaries of traditional scientific disciplines, innovating at the interfaces between mechanical, electrical, chemical, optical, and biological sciences. This transdisciplinary engineering approach enables Sciperio to jump quickly from innovation to product realization.  Through two decades of pioneering work for our manufacturing arm, nScrypt, in areas including bioprinting, 3D manufacturing (aka Direct Digital Manufacturing), and printed RF electronics, we seek to promote technology for the betterment of humankind.  www.sciperio.com.

CONTACT:
Brandon Dickerson
nScrypt Inc.
Email: bdickerson2@nscrypt.com
Phone: (407) 275-4720