Purchasing & Materials Management

Purchasing's main challenge is to requisition components and PWBs suitable for lead-free assembly and to balance the needs for parts with the myriad of lead finish, PWB surface finish and solder alloys currently available.

Although vendors are offering some components with lead-free lead finishes such tin, Pd/Ni, Au/Ni, and Pd/Au/Ni, purchasing will be far more restricted in terms of part availability than in the past. When attempting to purchase lead-free components, one may run into several obstacles: only a single-source for a
part, a part that is not quite suitable, a change in lead-times, significantly more expensive, or no source at all. To overcome these obstacles, Purchasing needs to work in close conjunction with Engineering/Design and vendors to ensure that the lead-free parts needed are available and compatible with the manufacturing process.

As with components, there is some availability of lead-free PWB surface finishes. OSPs, Au/Ni, Immersion Sn, Ag, and Lead-Free HAL finish PWBs have been on the market for some time now. Again, Purchasing needs to work in close conjunction with Engineering/Design and vendors to ensure that the
lead-free parts needed are available compatible with the manufacturing process.

The many component and PWB coatings, as well as several possible solder alloys results in a huge matrix of potential material intermix, and clearly can complicate materials management. More than ever, purchasing will need to be attuned to which parts go with which product. Once again, Purchasing must
work in close conjunction with Engineering to ensure that ordering is streamlined and that the appropriate parts are available for particular jobs.