Rugged Devices and Parylene
Posted by Sean Horn
Friday, April 24, 2015 9:00
@ 9:00 AM
The Need for Rugged Products
Designed for use under the most extreme and severe conditions, rugged products must function up-to-standard in environments characterized by punishing disparities of hot or cold, intensive vibrations, and disproportionate levels of dryness or moisture.
Because temperatures or atmospheric surroundings where rugged products need to be used are unusual, internal components of these specialized products are also subject to frequently unremitting challenges to function and performance. These circumstances compel levels of ruggedization similar to the products’ exteriors.
Rugged devices have demonstrated extreme utility for such purposes as:
- Military embedded systems where reliable functionality through extreme conditions is imperative, often for extended duration of in-field, on-site service;
- Aerospace computing, where components and devices are frequently subjected to exceptional compression / stress, radical changes in temperature, and variable atmospheric conditions (or lack of them) when spacecraft / aircraft are in flight;
- Specialized scientific research or undersea / arctic exploration / surveying; and
- Varieties of public safety, field service, emergency healthcare, transportation/distribution, and commercial functions.
The objective of ruggedization is providing a controlled environment for the device’s installed electronics. Protecting delicate, finely-tuned components requires conformal coatings of exceptional performance durability and versatility.
Parylene Conformal Coatings for Rugged Devices
Rugged products use electrical components selected as much for their robustness and resilience as their functional capacities during normal use. They will operate as expected through extreme changes in temperature, wind velocity and similar abnormal environmental conditions.
However, the reliability of the protective coatings selected to conform to their surfaces needs to be unquestionable, consistently shielding components and exteriors, without impeding their functionality.
Parylene not only generates the required safeguards for environmental circumstances, but also helps assure the go-anywhere productivity that is the object of the device’s use. This ability is imperative for many military / aerospace applications, where:
- Equipment failure is not an option,
- Wireless connectivity must be dependable and fast , and
- Monitor displays must remain readable under all outdoor / in-flight / undersea conditions.
Parylene solutions have a wide selection of variants, but the most commonly used are C, N, and AF-4. Of these parylene C is used most commonly. When parylene coating, the technician places the item to be protected in a special deposition chamber. Vaporized parylene dimer deposits itself onto the item, creating a protective coat that covers it entirely — even under parts and inside gaps. The coating provides a high degree of protection but is extremely thin — usually measured in microns — and essentially invisible. In addition, environmental settings characterized by material intrusions of water, wind, dust, or moisture, are suitably protected.
The result is a coating that can help the rugged device perform at MIL STD 810 standards. Parylene protection rugged devices ensures functional resistance to such widely divergent circumstances as rapid changes in temperature, excessive humidity, alterations in altitude, and interference generated by magnetic properties or radio frequencies.
Ruggedized parylene protection maintains functional resistance to harsh environments that would shut-down unprotected devices. Manufactured specifically to meet challenging performance standards, their use is growing, even as their ability to match expanded operational expectations improves.