-
- News
- Books
Featured Books
- design007 Magazine
Latest Issues
Current IssueLevel Up Your Design Skills
This month, our contributors discuss the PCB design classes available at IPC APEX EXPO 2024. As they explain, these courses cover everything from the basics of design through avoiding over-constraining high-speed boards, and so much more!
Opportunities and Challenges
In this issue, our expert contributors discuss the many opportunities and challenges in the PCB design community, and what can be done to grow the numbers of PCB designers—and design instructors.
Embedded Design Techniques
Our expert contributors provide the knowledge this month that designers need to be aware of to make intelligent, educated decisions about embedded design. Many design and manufacturing hurdles can trip up designers who are new to this technology.
- Articles
- Columns
Search Console
- Links
- Events
||| MENU - design007 Magazine
Failures and Reliability in Soldering
July 9, 2019 | Michael Gouldsmith and Zen Lee, ThermaltronicsEstimated reading time: 3 minutes
- Intermetallics are frequently brittle, and differences in CTE (coefficient of thermal expansion) between intermetallic and solder can contribute to internal stress
- Depletion of one element of the surface may impair solderability
Figure 2: Cross-section showing the two distinct intermetallics between the copper and tin.
Nevertheless, without an intermetallic layer, there is no valid soldering joint, and once created, the layer grows at any temperature and accelerates exponentially as temperatures increase. This growth continues until the intermetallic compounds (the base metal) occupy the entire joint, and/or the solder is exhausted.
The rules for good solder joints are:
- Solder as quickly as possible
- Use the lowest possible soldering temperature that yields acceptable joints
- Avoid repeated soldering to improve the appearance of the joint since added exposure to high temperatures only increase the intermetallic layer. The joint may look pretty but is weaker or stressed
- Remember that the intermetallic layer grows at any temperature but accelerates exponentially at elevated temperature levels. Rates of dissolution of various metals also will rise with increases in temperature
Reliable Solder Technique
Having established what considerations are necessary to form a reliable solder joint, the next step is to understand how to achieve this and what processes should be followed. While much of the focus in soldering is placed on the tip idle temperature, solder joint temperature is more relevant than of the “no-load” tip idle temperature.
To read the full article, which appeared in the July 2019 issue of SMT007 Magazine, click here.
Page 2 of 2Suggested Items
Indium Corporation Expert to Present on Pb-Free Solder for Die-Attach in Discrete Power Applications
04/30/2024 | Indium CorporationIndium Corporation Product Manager – Semiconductor Dean Payne will present at the Advanced Packaging for Power Electronics conference, hosted by IMAPS, held May 8-9 in Woburn, Massachusetts, USA.
Taiyo Circuit Automation Installs New DP3500 into Fuba Printed Circuits, Tunisia
04/25/2024 | Taiyo Circuit AutomationTaiyo Circuit Automation is proud to be partnered with Fuba Printed Circuits, Tunisia part of the OneTech Group of companies, a leading printed circuit board manufacturer based out of Bizerte, Tunisia, on their first installation of Taiyo Circuit Automation DP3500 coater.
Vicor Power Orders Hentec Industries/RPS Automation Pulsar Solderability Testing System
04/24/2024 | Hentec Industries/RPS AutomationHentec Industries/RPS Automation, a leading manufacturer of selective soldering, lead tinning and solderability test equipment, is pleased to announce that Vicor Power has finalized the purchase of a Pulsar solderability testing system.
AIM Solder’s Dillon Zhu to Present on Ultraminiature Soldering at SMTA China East
04/22/2024 | AIMAIM Solder, a leading global manufacturer of solder assembly materials for the electronics industry, is pleased to announce that Dillon Zhu will present on the topic: Ultraminiature Soldering: Techniques, Technologies, and Standards at SMTA China East. This event is being held at the Shanghai World Expo Exhibition & Convention Center from April 24-25.
AIM to Highlight NC259FPA Ultrafine No Clean Solder Paste at SMTA Wisconsin Expo & Tech Forum
04/18/2024 | AIMAIM Solder, a leading global manufacturer of solder assembly materials for the electronics industry, is pleased to announce its participation in the upcoming SMTA Wisconsin Expo & Tech Forum taking place on May 7 at the Four Points by Sheraton | Milwaukee Airport, in Milwaukee, Wisconsin.