NPL defect of the month

10 November 2010 Manufacturing / Production Technology, Hardware & Services News

Secondary reflow of lead-free joints is not an uncommon defect found in manufacture.

X-ray inspection of a lifted J-lead (as shown in the accompanying image) was part of an investigation to pinpoint the possible cause of open joints. In this case a known amount (9-10%) of lead was present on the lead plating in these lead-free joints.

Control of board temperature is very important during wave soldering to avoid secondary reflow on the topside of the board. This can occur when a board passes over the solder wave and the heat is transferred through the bulk of the board by conduction. Correct topside profiling can eliminate this issue by use of a process control tool to monitor changes in contact time and temperature.

It is understood that some companies have experienced problems over the last couple of years with secondary reflow of lead-free joints during wave soldering. This has led to separation of the termination from the bulk of the joint. In the past the same phenomenon has occurred with traditional tin/lead alloys when the top surface of the board reached or exceeded 180°C. Research work at NPL has examined the level of lead contamination and its impact on reliability. It has demonstrated that small amounts of lead will lower the reflow temperature of lead-free alloys (217-221°C) leading to secondary reflow at tin/lead reflow temperatures (183-184°C).

It is very important to check components for lead contamination to reduce the possibility of secondary reflow due to a low temperature phase and to meet the requirements of RoHS.

This month’s featured NPL defect video covers the topic of damaged components during intrusive reflow – view it online at www.dataweek.co.za/video.

Further reading:

Find high-quality flex and rigid-flex PCBs at PCBWay
PCBWay Manufacturing / Production Technology, Hardware & Services
[Sponsored] Flex and rigid-flex PCBs are widely used across various industries due to their unique combination of flexibility, durability, and design versatility. Among the leading providers, PCBWay stands out for its exceptional quality services.

Read more...

---

The ultimate range for design and repair
RS South Africa Manufacturing / Production Technology, Hardware & Services
Whether adapting existing systems or maintaining essential equipment, design and repair play a crucial role in ensuring efficiency and longevity.

Read more...

---

Next-generation SPI and AOI series
Techmet Manufacturing / Production Technology, Hardware & Services
Saki Corporation has launched its next-gen series for SPI and AOI featuring a modular design for enhanced inspection efficiency and automation.

Read more...

---

Yamaha’s Advanced Safety Package eases factory-safety
Truth Electronic Manufacturing Manufacturing / Production Technology, Hardware & Services
Yamaha Robotics SMT Section has extended availability of the Advanced Safety Package, which contains optional features to elevate printer and mounter safety above and beyond mandatory levels.

Read more...

---

Case Study: Siemens Valor automation solution
ASIC Design Services Editor's Choice Manufacturing / Production Technology, Hardware & Services
Electronics manufacturer BMK used Siemens Valor to enhance accuracy and speed up bill-of-materials quotations.

Read more...

---

The factory beat
Electronic Industry Supplies Manufacturing / Production Technology, Hardware & Services
Change is the only constant across today’s complex manufacturing landscape. The surge of digital transformation, spearheaded by Industry 4.0, has redefined how factories operate, build, and evolve.

Read more...

---

Microtronix powers up 2025 with smart meter production for Eskom
Microtronix Manufacturing Manufacturing / Production Technology, Hardware & Services
Microtronix has kicked off 2025 with a significant milestone: the production of smart meters for Eskom, designed to assist customers with load reduction initiatives.

Read more...

---

Reliable X-ray inspection system
MyKay Tronics Manufacturing / Production Technology, Hardware & Services
Inspecting long PCBs that are often used in sectors like telecommunications, automotive, and energy, where high reliability is required, presents several unique challenges.

Read more...

---

G-Tera high-speed SMT printer
Techmet Manufacturing / Production Technology, Hardware & Services
The new generation of automatic printing presses from GKG, the all-new G-Tera, is equipped with a 3,0-megapixel LIGHT-Bolt CCD camera, an upgraded conveyor system, and an enhanced printing system.

Read more...

---

Extending AI assistance in AOI
Yamaha Motor Europe N.V. Manufacturing / Production Technology, Hardware & Services
Artificial Intelligence is renowned for image recognition and classification skills, suggesting a great fit with the objectives of automatic optical inspection.

Read more...

---