Eddie Brunker wrote:
>
> At 16:10 30/04/98 -0700, you wrote:
> >TechNet,
> >
> >As we all know HASL has been the work horse in the industry for several
> >years as an excellent surface finish.
>
> >The problem is the lead content as
> >it pertains to hazard waste,
>
> I wasn't aware there was a hazardous waste from the use of lead in assembly.
> The unused paste and wave solder dross can all be recycled, so where is the
> problem after that?

This is not such a simple issue.  There is some speculation
that the soldered joints of discarded electronics in landfills
can be leached by acid rain and pollute ground water.  I have
yet to see a convincing fate study to prove this.  My best guess
would be that most of the lead pollution in ground water and soil
today is still from the tetraethyl lead that was used in
gasoline decades ago, and that lead pollution owing to PCB solder
leachate is a very small fraction of the total.  However, I am not
a soil chemist.

>
> > which is forcing the electronic industry to
> >find an alternative.
>
> Who is doing the forcing? Is there a world wide organization putting
> pressure on assembly companies to remove lead from the assembly process? Who
> outside the electronics industry (politicians, academics, the man on the
> street..etc.) is aware or considers that lead is used in the assembly process?

I would think that good fraction of the general population
knows that solder is used in PCB manufacture and solder contains
lead.

>
> What are the facts regarding the hazards of lead in assemblies?
>
> Is this pressure coming from organizations in electronics assembly nations
> such as Malaysia, Taiwan, Ireland, Mexico.....?
>

The pressure is coming from Scandinavia, where electronics
assembly must be lead-free in the near future.  Nokia and
Ericsson have electronic assembly plants there.  Some of the
other European countries are reluctantly considering lead-free.
US and Japanese PCB manufactuers are interested in lead-free
assembly because they want to sell products in Europe.

> Do you have an alternative to soldering with lead? If so can you share the
> process details with us all?
>
> Eddie

There are currently lead-free processes, but they are new
and process details and problem are not nearly as well
understood as near-eutectic Sn/Pb.
>
> >
> >We are in the process of evaluating alternative surface finishes:
> >
> >1.)  Florida CirTech's OMIKRON process(Tin)
> >2.)  Alpha Metal's Alpha Level
> >3.)  DEXTER's product
> >
> >I would greatly appreciate any and all feed back as it pertains to any
> >alternatives to HASL.   Your responces would be greatly appreciated.
> >Please keep in mind the following items:
> >
> >1.)  SIR Testing
> >2.)  Electromigration
> >3.)  Solder Wettability
> >4.)  Heat Cycling
> >5.)  Aging Test
> >6.)  Reworkablity
> >7.)  Ionic Contamination

AlphaLevel passes Bellcore SIR and Electromigration tests
alone and with no clean flux. It is highly solderable, but
not as solderable as a good HASL finish.  More information
can be obtained from AlphaMetals in Irvine CA.

I'm sure Florida CirTech and Dexter would be happy
to provide you with technical information on their products.

> >
> >Thank you for your responses,
> >
> >Nate Natzke
> >[log in to unmask]
> >
> >Tri-Star Engineered Products, Inc.
> >351 Thor Place
> >Brea, CA 92821
> >
> >Phone: (714) 671-1545
> >Fax:   (714) 671-1124

################################################################
TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c
################################################################
To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body:
To subscribe:   SUBSCRIBE TechNet <your full name>
To unsubscribe:   SIGNOFF TechNet 
################################################################
Please visit IPC web site (http://jefry.ipc.org/forum.htm) for additional information.
For the technical support contact Dmitriy Sklyar at [log in to unmask] or 847-509-9700 ext.311
################################################################