-
- News
- Books
Featured Books
- smt007 Magazine
Latest Issues
Current IssueBox Build
One trend is to add box build and final assembly to your product offering. In this issue, we explore the opportunities and risks of adding system assembly to your service portfolio.
IPC APEX EXPO 2024 Pre-show
This month’s issue devotes its pages to a comprehensive preview of the IPC APEX EXPO 2024 event. Whether your role is technical or business, if you're new-to-the-industry or seasoned veteran, you'll find value throughout this program.
Boost Your Sales
Every part of your business can be evaluated as a process, including your sales funnel. Optimizing your selling process requires a coordinated effort between marketing and sales. In this issue, industry experts in marketing and sales offer their best advice on how to boost your sales efforts.
- Articles
- Columns
Search Console
- Links
- Events
||| MENU - smt007 Magazine
Tips & Tricks: Water Contamination and Flux Expiry
April 17, 2019 | Jason Fullerton, MacDermid Alpha Electronics SolutionsEstimated reading time: 1 minute
First, can water contamination cause failure? Absolutely! Rainwater contains much higher electrochemically active content than the deionized water used for cleaning PCB assemblies and can lead to corrosion and dendritic growth. If discovered before introduction to the service environment, cleaning may be possible, and the assemblies may be able to be salvaged. Exposure to rainwater in the service environment is a sure path to failure unless the assembly has been ruggedized against such exposures as part of the design.
Second, how do you know if a flux is bad and shouldn’t be used? Flux is a chemical that reacts with oxides that naturally form on metal surfaces. When flux cannot adequately react with the metals that are to be joined, a solder joint does not form properly. Even with fluxes that are properly stored, time can reduce the ability of a flux to perform that intended function.
Third, are there any simple tests for this? A good quantitative test for liquid fluxes is the acid number, and an acid number below the flux’s particular minimum specification is a key indication that a flux should not be used. Otherwise, qualitative testing of a flux’s soldering performance is common to resolve suitability for use after a question. Each form of flux has its own solderability tests that can be performed, but they all boil down to “Does the flux work or not?”
A higher level of defects and reduced soldering performance is to be expected when too-old fluxes are used. Solder joints that form properly are not expected to exhibit reduced reliability. However, a higher number of defects created tends to lead to a higher chance that defective connections escape detection through inspection and functional testing, and that’s not a risk to be taken lightly.
Jason Fullerton is the customer technical support engineer at the Assembly Division of MacDermid Alpha Electronics Solutions.
Suggested 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.