-
- News
- Books
Featured Books
- smt007 Magazine
Latest Issues
Current IssueCertifications
Certifications have historically been seen as a cost of doing business, but how do we turn them into a positive ROI and a value to both customer and vendor?
The Butterfly Effect
The basis of chaos theory is a key concept known as the “butterfly effect.” It’s the idea that a small event in one place creates a cascading set of events elsewhere. So, how is the EMS landscape changing? We’re tracking the concerns and dynamics of this landscape, and there’s a lot to learn.
Coming to Terms With AI
In this issue, we examine the profound effect artificial intelligence and machine learning are having on manufacturing and business processes. We follow technology, innovation, and money as automation becomes the new key indicator of growth in our industry.
- Articles
- Columns
Search Console
- Links
- Events
||| MENU - smt007 Magazine
BOOK EXCERPT: The Printed Circuit Assembler’s Guide to... Encapsulating Sustainability for Electronics, Chapter 2
July 3, 2024 | I-Connect007 Editorial TeamEstimated reading time: 1 minute
The following is a brief excerpt from: The Printed Circuit Assembler’s Guide to... Encapsulating Sustainability for Electronics
By Beth Turner, MacDermid Alpha Electronics Solutions
Chapter 2: Application Overview
There are many important things to consider when applying an encapsulant. This chapter is an overview of the application process, we will cover many of the terms and definitions found on a technical data sheet and discuss the primary considerations for each of the process stages. It is worthwhile considering some of the terms and definitions found on a technical data sheet to understand how the different liquid, mixed system, and cured property values can dictate the method chosen to apply materials.
Storage
It is important to store liquid encapsulants according to the manufacturer’s specification to ensure shelf lives are achieved. Single component materials require external energy sources to initiate the curing reaction; heat-cure systems should be stored in cool, often sub-ambient temperatures; UV-cure systems should be stored in blackout containers to prevent premature curing. Partial curing can increase the viscosity and cause small gelatinous clumps to form in the liquid system; this can cause problems during the application, for example, blocking valves and lines in dispensing equipment. Some liquid encapsulants are sensitive to moisture; it is important to keep such encapsulants stored in airtight containers. In addition to the problems above, moisture contamination can also cause unwanted side reactions during the cure process that can lead to undesirable bubbles and voids.
The Liquid Properties
When asked, “What is the viscosity,” the short answer is, “It depends.” Most encapsulants in their liquid state exhibit non-Newtonian flow and thus viscosity is not a single number. Viscosity is dependent on a variety of factors, including temperature, shear rate, time, and volume. Rheology profiling could be a more useful tool to understand liquid flow properties.
It is also important to understand the density of the material to convert between the weight and volume mix ratio, but also to understand the weight contribution an encapsulant will have, to a PCBA or unit.
Suggested Items
Air Liquide Signed Major Contract to Support the Semiconductor Industry in the U.S.
06/07/2024 | Air LiquideAir Liquide will build a new industrial gas production facility in the United States to supply the new fab of one of the world’s leading semiconductor manufacturers.
Molex Releases Report on Thermal Management Challenges and Opportunities for I/O Modules
05/22/2024 | PRNewswireMolex, a global electronics leader and connectivity innovator, has published a report that examines thermal management pitfalls and possibilities as data center architects and operators strive to balance high-speed data throughput requirements with the impacts of growing power density and the need for heat dissipation on critical servers and interconnect systems.
The Delicate Balance of Sustainable Business and Going Green
03/25/2024 | I-Connect007 Editorial TeamAlex Stepinski is known throughout the industry as an innovator and disruptor committed to environmental sustainability, primarily through his current work around zero liquid discharge (ZLD) for PCB fabrication. But Alex says financial sustainability must come first. Standing firm in his belief that green is the most financially sustainable option for manufacturing and financial success, he explains his position and vision for a greener, more lucrative future for bare board fabricators. “Before I retire in about 10 years,” he says, “I want to make sure that all new fabs, and at least 25% of the old ones are zero liquid discharge in this industry.”
Foxconn Showcases AI Solutions for Servers, EV Driving at NVIDIA GTC
03/20/2024 | FoxconnHon Hai Technology Group (Foxconn), the world’s largest electronics manufacturing and service provider, announced its participation at NVIDIA GTC, showcasing the Group’s robust expertise in AI solutions that span exclusive, state-of-the-art server systems, advanced driver assistance systems for intelligent electric vehicles and groundbreaking deep learning research for autonomous driving called “QCNet.”
Hernon Manufacturing Redefines Pipe Thread Sealant Dispensing with Autobond® Line
02/27/2024 | Hernon Manufacturing, Inc.Hernon is pleased to offer its Autobond® line of dispensers, specifically designed for the precise application of sealants. The Autobond® line of dispensers, developed by Hernon's equipment division, is engineered to deliver metered amounts of sealant directly to male fittings, ensuring accurate and efficient application while minimizing product waste.