Manufacturing / Production Technology, Hardware & Services


The transition to lead-free solder

20 September 2006 Manufacturing / Production Technology, Hardware & Services

The electronics industry has grown up with tin/lead solder. The IEC defines these alloys as Sn60Pb40A, Sn63Pb37A or Sn62Pb36Ag02B. Over four decades the long-term performance of tin/lead alloys has been intensely studied. The IEC and IPC have issued comprehensive documentation, standards and test methodologies that allow manufacturers to ascertain the reliability of their electronics assemblies.

Lead is now banned from electronics assemblies intended for sale in the EU. Legislation of a similar nature is likely to be introduced in Japan, California and China. Both IEC and IPC committees are working hard to try and ensure that revisions to the existing standards are published as quickly as possible, but neither group will have published documents until late 2006. However, both the IEC and IPC are recommending high tin alloys as the best replacements for tin/lead.

Specifically, the IEC states: "The preferred alloy composition should be either Sn96.5Ag3.0Cu0.5 or Sn99.3Cu0.7. An alloy consisting of 3-4% Ag and 0,5-1% Cu with the remainder made up of Sn may also be used instead of Sn96.5Ag3.0Cu0.5. A solder alloy comprising 0,45-0,9% Cu with the remainder made up of Sn may be used instead of Sn99.3Cu0.7."

IPC states: "The solder composition shall be tin (Sn)96.5 silver (Ag)3.0 copper (Cu)0.5 (SAC305) as defined by J-STD-006". The IPC does allow other lead-free solder alloys if agreed between user and vendor.

High tin alloys have not been as well characterised as traditional tin/lead solders. While the IEC and IPC have been rapidly assimilating data on the long-term performance of lead-free alloys it will be some time before comprehensive information is available. Accordingly, both the IEC and IPC are defining thorough testing regimes - with acceptable Gauge R & R - for manufacturers whose products will be used in safety critical applications.

Defining new test methods is critical because the reliability of electronics hinges on the performance of the solder.

Gen3 Systems manufactures the Must System Solderability Tester for wetting balance force measurement and globule testing. The equipment is ideal for both tin/lead and lead-free alloy testing and has been used by the industry for many years. The company has also produced a lead-free bath and globule set and lead-free accessories kit to allow existing Must Solderability Tester owners continuing use of their equipment.

For more information contact Graham Naisbitt, +44 (0)12 5252 1500, [email protected]

Graham Naisbitt is a member of the IEC’s TC91 WG3, the working group that formulates test standards for the assembly industry. He is also Leader of Solderability Testing Standard IEC 60068-2-69, Co-leader of Solderability Testing Standard IEC 60068-2-54, and Member of IPC-J-STD 002 and IPC-J-STD 003.





Share this article:
Share via emailShare via LinkedInPrint this page

Further reading:

Solar to the rescue amid Eskom tariff hikes
Manufacturing / Production Technology, Hardware & Services
Steep electricity tariff hikes mean South African consumers are still battling electricity woes, making the switch to solar more sensible than ever.

Read more...
Optimising cleaning products used in electronics manufacturing
Manufacturing / Production Technology, Hardware & Services
IPC, in collaboration with ChemFORWARD, are hosting a webinar titled ‘Optimising Cleaning Products Used in Electronics Manufacturing’.

Read more...
Webinar: Rapidly create vision-based edge AI solutions
Manufacturing / Production Technology, Hardware & Services
This webinar will give attendees an overview of the development kit, and will teach how it can be leveraged with Avnet’s IoTConnect platform, to rapidly develop cloud-connected solutions.

Read more...
Webinar: End-to-end ML model development
Manufacturing / Production Technology, Hardware & Services
Whether attendees are just starting out, or looking to refine their existing skills, this webinar is the next step to becoming proficient in creating machine learning models that solve real-world problems.

Read more...
PCBWay: Your one-stop shop for electronics manufacturing from design to production
PCBWay Manufacturing / Production Technology, Hardware & Services
[Sponsored] PCBWay has a long history of providing manufacturing support and design advice based on our customers’ products, and we continue to provide our customers with printed circuit boards, components, PCB assembly, moulding services, electronic assemblies, contract manufacturing, etc., from design to mass production.

Read more...
Yamaha accelerates transition to next-gen vehicle lighting
Truth Electronic Manufacturing Manufacturing / Production Technology, Hardware & Services
Europe’s automotive lighting makers are moving away from traditional electrical production techniques to become high-speed, precision electronic assemblers.

Read more...
Eight ways temporary solder mask is used for electronic assembly
Allan McKinnon & Associates Editor's Choice Manufacturing / Production Technology, Hardware & Services
While it is most used to mask open vias in a wave soldering process, operators find all kinds of creative ways to use solder mask to solve process challenges.

Read more...
Smart AOI provides essential inspection
Testerion Manufacturing / Production Technology, Hardware & Services
TRI has introduced the Core Features 3D AOI, the TR7700QC SII, which is equipped with essential inspection functionalities tailored for the electronics manufacturing industry.

Read more...
Newest mounter designed for the autonomous factory
Techmet Manufacturing / Production Technology, Hardware & Services
Panasonic has now started accepting orders for its newest modular mounter NPM-GW. This mounter is designed to enhance production lines with the end goal of having a fully functioning autonomous factory.

Read more...
Autonomous labour-saving factory solution
Techmet Manufacturing / Production Technology, Hardware & Services
With predictive and targeted maintenance options to maximise uptime, the NPM-GH from Panasonic is the first step to a truly autonomous factory.

Read more...