A31. Yes, but there is the potential for poor alignment and open joints. Since the usual SnPb reflow profile may not exceed the melting point of the BGAs’ lead-free solder balls, the SnPb solder paste melts but the SnAgCu solder balls do not. The lack of ball collapse may cause a lack of contact between the solder paste and the solder ball.

Reflow soldering: SnAgCu, SnAgCuBi, SnAg, SnAgBi, SnZnBi, SnIn (the bismuth-containing solders are more suitable for low temperature soldering) Wave Soldering: SnAgCu, SnCu, SnCu(Ni 0.1%), SnCuX, where X is the small fraction of elements claimed to increase performance A13. No suitable alternative has yet been identified for this solder which melts at around 302OC.

Since there is higher tin content, with higher temperature and presence of more active flux, the erosion of soldering tips occurs faster than regular tin/lead solder.

A17. Yes, the process window is markedly narrower with lead-free soldering. A particular concern lies with the ability of the reflow ovens to provide the smaller deltaT necessary. Some manufacturers have successfully used nitrogen inerting during soldering to widen the process window. There should be no changes in process control required for printing, placement and inspection of lead-free product.

The following machines , equipments and tools have been introduced to carry out the lead-free production, The lead-free project has been underway since 2003, We've assigned engineers and technicians to attend various trainings, lectures and seminars on lead-free technology.

Altera does not have a set schedule to introduce lead-free solder bump flip-chip products at this time. Internal solder bumps are exempted from the RoHS Directive until 2010, and Altera is closely monitoring the industry progress with a plan to start qualification in the near future. Home | Products | Support | End Markets | Technology Center | Education & Events | Corporate | Buy On-Line

SnPb leadframe plating can be used with certain Pb-free solder pastes, as shown in the following table: Melting point 138°C; Not recommended –relatively weak joint strength when subject to temperature cycling; compatible with 100% matte tin finishes; not compatible with existing SnPb finishes Melting point 183°C; common use for electronic applications; compatible with 100% matte tin finishes; shiny appearance Melting point 219°C; compatible with existing SnPb finishes and 100% .

Higher melting point of Lead-free solder may cause physical and thermal damage to components and PCB.

Yes. The leads on new parts for the most part are coated with pure tin, which solders normally. Just make sure you buy some old-fashioned solder before IT goes away!

A18. Yes, for example, maintaining the composition of the solder bath, and advice should be sought from your solder and equipment suppliers. For example, the copper levels must be taken into account when replenishing the solder bath, and copper dissolution of the tracks and pads can result in their being less than the minimum acceptable thickness.

A33. Yes, but they are not likely to be great and many will be of a one-off nature. Initial costs may include new equipment purchase (where necessary), existing equipment modification (for higher temperatures, inerting etc), implementing new inspection procedures, training and stock control. On-going costs may include those associated with tighter process control and increased power consumption from higher temperature soldering.

Harris Products Group has several lead-free solders, including: Stay-Brite®, Stay-Brite® 8, Bridgit® and 95/5.

Due to the higher melting temperature of lead-free soldering material soldering profiles have to be adjusted accordingly. You may find information on that subject e.g. in the IEC Standard 60068-2-58.

Soldered surfaces must be free of lead to begin with. This includes the PCB as well as the component. Lead contamination on a lead-free solder joint will significantly reduce the reliability of the joint. All lead-free alloys melt at a higher temperature than traditional tin-lead alloys. The temperature of the soldering iron may need to be increased, and both the components and PCB will need to withstand these higher levels.

Primarily NEMI and IPC in the United States and Soldertec and Smartgroup in Europe. NEMI, which develops technology “roadmaps” for the electronics industry, identified a gap in the manufacturing infrastructure necessary for conversion to lead free in the early 1990’s when the first WEEE draft appeared. Since then NEMI has been instrumental in providing leadership and coordination to facilitate the conversion to lead-free.

The elements mercury, cadmium and its combinations, as well as hexavalent chromium may be contained in traces below the threshold defined by law. PBB as well as PBDE, in particular special Ocata- and pentabrominated diphenylethers, have been eliminated from production during the last years.

A20. If your boards already require cleaning, then you will need to continue to clean boards assembled using the new lead-free solders. But the cleaning may be more challenging, since there will probably be more corrosive residues present, and they are likely to be more tenacious and baked-on. If you already have a no-clean process, you will probably not need to clean using your new lead-free process.

A11. No, you will have to change your process to some degree. The choice is not necessarily straightforward, and will depend on the application, thermal and temperature factors, assembly technology, component thermal sensitivity, service life, volume, cost etc. However, there is an increasing consensus for using the SnAgCu family of alloys for many applications for both reflow and wave soldering.

Customers may continue to buy products that have not been "converted" subject to availability in either format, with SnPb Lead Finish or Lead Free. If other products are converted, advanced notification will be given. Should a major customer require product with SnPb plating after a general product conversion, a Customer Special Part Number may have to be generated. The length of time the old product will remain available to you will be by special agreement. (Pricing may then be reviewed.

Any fuel gas lines installed using copper tube must be brazed using a filler metal containing less than 0.05% P (phosphorus) and a melting temperature greater than 1000 degrees F. The only filler metal (trade and industry standard) that contains less than the 0.05% P would be an AWS BAg type alloy (according to the American Welding Society’s AWS A5.8 specification). In no case should solder or “soft-solder” be used to join copper tube and fittings in fuel gas systems.