Standard of Excellence: The Perfect PCB Fab—A Vision for Five Years Ahead
Facing the Future: Engaging a New Generation
Global Sourcing Spotlight: Get Out of China? It’s Quite ComplexHigh Reliability Thanks to Adhesives
April 8, 2015 | Kevin Balben, DELOEstimated reading time: 1 minute
Protecting electronic components from thermal, mechanical and chemical stress is becoming increasingly important in many industries.
While application-friendly packaging is one way to ensure components’ stability, highly reliable encapsulants are playing a more important role as well.
DELO Industrial Adhesives’ product specialist Kevin Balben explains the correct uses of today’s encapsulants and compounds and clarifies the myths that surround them.
True or False?
When using encapsulants and casting compounds in electronic production, there is no alternative to heat curing in ovens.
True. While users have a choice between heat curing and light curing, the latter is used in a handful of applications including those that use connectors, switches and relays. Light curing acrylates are ideal for these applications and enable extremely short cycle times.
As soon as components are exposed to harsh environmental conditions, heat-curing epoxy resins are the only game in town. These robust products contain an anhydride hardener activated by heat. Therefore, curing requires temperatures between +100°C and +180°C.
For demanding conditions there are no alternatives to heat curing. Thermodes and induction are forms of heat curing and work faster than a normal oven, but are still slower than light curing. Users cannot always use induction or thermodes because the geometry and size of the parts may not allow it. For the most part, there is no way around air convection ovens.
Temperature and freedom from tensions are conflicting goals when trying to optimize the curing process.
True. The higher the temperature, the faster the adhesive cures. Thus, high temperatures are good for fast processes. At the same time, high tension causes a great deal of warping since the polymer network is created through heat and shrinks during cooling.
If warping is too intense, the materials should be cured at lower temperatures for a few minutes more. Unfortunately, there is no rule of thumb, so keep in mind that every component and assembly must be assessed individually.
Editor's Note: This article originally appeared in the March issue of SMT Magazine.
Share on:
Suggested Items
The Drive Toward UHDI and Substrates
09/20/2023 | I-Connect007 Editorial TeamPanasonic’s Darren Hitchcock spoke with the I-Connect007 Editorial Team on the complexities of moving toward ultra HDI manufacturing. As we learn in this conversation, the number of shifting constraints relative to traditional PCB fabrication is quite large and can sometimes conflict with each other.
Standard Of Excellence: The Products of the Future
09/19/2023 | Anaya Vardya -- Column: Standard of ExcellenceIn my last column, I discussed cutting-edge innovations in printed circuit board technology, focusing on innovative trends in ultra HDI, embedded passives and components, green PCBs, and advanced substrate materials. This month, I’m following up with the products these new PCB technologies are destined for. Why do we need all these new technologies?
Experience ViTrox's State-of-the-Art Offerings at SMTA Guadalajara 2023 Presented by Sales Channel Partner—SMTo Engineering
09/18/2023 | ViTroxViTrox, which aims to be the world’s most trusted technology company, is excited to announce that our trusted Sales Channel Partner (SCP) in Mexico, SMTo Engineering, S.A. de C.V., will be participating in SMTA Guadalajara Expo & Tech Forum. They will be exhibiting in Booth #911 from the 25th to the 26th of October 2023, at the Expo Guadalajara in Jalisco, Mexico.
Intel Unveils Industry-Leading Glass Substrates to Meet Demand for More Powerful Compute
09/18/2023 | IntelIntel announced one of the industry’s first glass substrates for next-generation advanced packaging, planned for the latter part of this decade.
Facing the Future: American Manufacturing on the Rise
09/18/2023 | Aidan Salvi -- Column: Facing the FutureI have been in and around circuit boards most of my life. I started 20 years ago in my family’s PCB shop, leaving after a couple of years to start my own software company. About a year ago, I returned to the family business, and the first thing I noticed was that nothing had really changed. We were doing the same things in the same way as the day I left. After talking to several experts in the industry, I realized it was worse than that: The manufacturing of PCBs had not changed in 70 years.