[PinkFloyd]

I have just read Graham Slee's article on the crazy European Lead free solder directive about to come into force in 2006. Is this directive a good move, considering Graham's stark warning, or should the eurocrats ditch this crazy idea in favour of public safety? (ie: planes falling out of the sky, weapons malfunctioning, computers failing etc. etc. due to lead free solder issues)

Grahams article is at: http://www.gspaudio.co.uk/legislation/rohsomission.htm

He's given me permission to recreate it here:

[size=medium]ROHS Directive

Glaring Omission

The Disintegration Of Tin

Home > Legislation Home > ROHS Glaring Omission


What is the most important metal to mankind? Gold? Silver? Platinum?

No! It's an alloy called Solder

We rely on so many items of technology for our survival, quality of life and dignity. Examples are: The Telephone; The Radio, The Television, The Motor Vehicle, The Mobile Phone, The Computer, The Train, The Ship, The Aeroplane, The Hearing-Aid, The Hospital Scanner, The Heart Pacemaker and the Electricity Supply.

All these rely on Solder.

Solder is an alloy of Lead and Tin. For Electronics the ratio is 40% Lead and 60% Tin.

It began in Roman times. The Romans used Lead pipes for water and joined them together by melting them.

Solder has been improved over many hundred years by adding Tin.

Today the world is connected together by Solder. It is fantastic to know that it holds together all those tiny micro components that distinguish us from the caveman.

The European Parliament has decided that from July 2006, this, the most important metal in the world, must have all the Lead removed, and that Solder will just be Tin, with a trace of Silver and/or Copper to give it half a chance of working.

Therefore, all of European Society will rely on an alloy containing 97% homogenous pure Tin.

The European Parliament has relied on two expert bodies for guidance: Soldertec and the Smart Group.

These bodies are considered to be experts on Tin.

However, many engineers and chemists understand something called allotropy. Tin is allotropic and below 13 degrees Celsius its allotropic form is a grey non-metallic powder. In other words, when it gets cold the Lead-free soldered joints disintegrate - bad news for mankind.

Admittedly it will take some time for this disintegration to take place. It will happen slowly at just below 13 degrees. But if exposed to severe cold like the winters we get in Northern Europe it will disintegrate much faster.

The electronics in your new car could fail to function after a few winters if they are soldered together with Lead-free solder. Your new car relies on electronics for your safety, for environmental protection and to make it go.

The car is just one of many examples.

I searched Google for allotropy in relation to the ROHS directive, Soldertec and Smart Group. These are the search results: -

Your search - rohs directive allotropy - did not match any documents.

Your search - www.lead-free.org allotropy - did not match any documents.

Your search - www.smartgroup.org allotropy - did not match any documents.

I searched Google for "allotropy of tin" and it came up with several thousand results. I selected a link from one of the results: - http://helios.physics.uoguelph.ca/su...les/scor40.htm

The last two paragraphs on this page read: -

Under certain conditions, gray tin can be a real problem. Gray tin is the stable form of tin at temperatures lower than 13 degrees C; above this temperature, the metallic form (white tin) is stable. When white tin is held for a long time at temperatures below 13 degrees C, it slowly changes into gray tin. The metallic surface becomes covered with a gray powder which is easily rubbed off. The gray patches gradually spread and eventually the object covered may totally lose its structural integrity and fall to pieces.

Because of the spreading nature of the condition, it is often known as tin disease or tin pest. In the cold cathedrals of northern Europe, tin disease was a particular problem in the last century when organ pipes were commonly made of tin. Tin disease was, on occasion, responsible for the complete disintegration of organ pipes in some of these cathedrals in long, cold winters.


I have known about this since when I researched Tin and Lead in the late 1970's. In the book "Inorganic Chemistry" David Abbott M.A., Ph.D., A.R.I.C; Mills & Boon, allotropy of Tin is described in section 9.31, pages 387-389. The grey allotrope is described as Tin-Plague and mention is made of Scott's tragic failed polar expedition, suggesting that the paraffin cans rotted because the protective tin coating disintegrated in the cold.

The author goes on to mention autocatalysis, which explains how the disintegration of Tin accelerates once the first seeds of grey Tin become established.

Much of the consumer electronics in our homes reach us after being shipped half way round the world in unheated containers. In colder waters in the depth of winter ice forms on these vessels. It is here where the seeds of destructive grey Tin will be sewn in consumer equipment. By July 2006 do not expect your modern technology purchase to work for very long.

It would seem the European Parliament and their expert advisors have no knowledge of grey-Tin and its consequences, and are ploughing on with the ROHS legislation in the same blissful ignorance for which Scott and his colleagues paid dearly with their lives.

Lead does not disintegrate and is one of the many good reasons why it is part of the alloy Solder. It makes soldered joints reliable. We owe Lead our gratitude for the safety and well-being modern technology affords to our lives.

The improvement to health and the environment through removing Lead from Electronic and Electrical Equipment will be so small that it will not be able to be quantified. Even the consultation paper of the ROHS directive issued by the UK Department of Trade and Industry says such improvements will be of limited benefit.

So, in the light of the above text, why are they doing it?[/size]

 

[chillysalsa]

It's an interesting area. Lead has also been shown to be a heavy metal toxin that, if ingested in sufficient quantities, can lead to brain damage and death... BUT, there are no data indicating environmental or health hazards posed by lead in printed wiring board manufacturing and electronics assembly.

Nevertheless, I can assure you with thousands of scientists (probably 100's of thousands!) are working on the lead-free problem and doing the most rigorous analysis of mechanical properties and long-term reliability of lead-free solders, an alloy prone to disintegrating at <13ºC would be an obvious problem!

As far as I know, the biggest problem in finding a substitute is an alloy that has a low enough melting point that will not damage components, the two candidates are: Sn-3.9Ag-0.6Cu (melts at 217C) for reflow soldering and Sn0.7Cu (melts at 229[degrees]C) for wave soldering. The regular Sn63-37Pb melts at 183C, so these are not 'drop-in' replacements.

Anyway, we will see what happens in Japan: they are on track to ban lead first, so we can see what affect it will have. I'm sure it gets cold there too!

 

[PinkFloyd]

So are Japan going to ban it before 2006?? From my understanding it will be illegal to manufacture or sell anything (in Europe) containing lead solder from July 2006. What the heck will happen to all the vintage gear that's in some of the audio shops will they have to resolder with this lead free stuff to avoid prosecution??

 

[nkd]

Mostly lies. I use lead free solder, and it's little different to the old kind. It just has a (slightly) higher melting point.

 

[guzzler]

the lead in solder is used to reduce the melting point, yes, but more historically importantly (in the electronics world), it makes solder flow much better, ie, it's a flux. The copper/tin solder which is now being introduced will have been tested under -13C, considering the vast majority of semiconductors and parts are specced -40 - 150C. The big problem for DIYers is the new solder is a swine to use, and requires a very high temperature bit, meaning you can't hold on for as long and the joint is less likely to be properly covered with solder. I've tried some lead-free solder and it is not fun to work with. However, machine soldering will be less affected, aside from having to upgrade the machinery for the higher temps needed. In regards to vintage gear, does this ban not only apply to new goods?

g

 

[00940]

Let's be a bit serious :

Quote:

Member States shall ensure that, from 1 July 2006, new electrical and electronic equipment put on the market does not contain lead, mercury, cadmium, hexavalent chromium, polybrominated biphenyls (PBB) or polybrominated diphenyl ethers (PBDE).

First it only concerns new product. It doesn't apply to things already on the market like vintage stuff and so on.

Quote:

exempting materials and components of electrical and electronic equipment from Article 4(1) if their elimination or substitution via design changes or materials and components which do not require any of the materials or substances referred to therein is technically or scientifically impracticable, or where the negative environmental, health and/or consumer safety impacts caused by substitution are likely to outweigh the environmental, health and/or consumer safety benefits

If lead is really needed to build critical stuff like cars or planes, they'll use it.

edit : the directive : http://europa.eu.int/eur-lex/pri/en/...en00190023.pdf

 

[aos]

Quote:

BUT, there are no data indicating environmental or health hazards posed by lead in printed wiring board manufacturing and electronics assembly.

Simply put, once electronics gets old and gets dumped into garbage pits, the lead will eventually make its way into water supply. That's why it's a concern.

 

[PinkFloyd]

Quote:

Originally Posted by aos Simply put, once electronics gets old and gets dumped into garbage pits, the lead will eventually make its way into water supply. That's why it's a concern.

lead comes out of the earth in the first place, it's not man made. Also, there are 600 million homes in Europe that have lead flashing on their roofs so everytime it rains lead finds its way into the water system.

Aeroplanes will be exempt from the directive but cars, computers etc. will not be so you can expect premature failure of engine management units, computers and other essential items.

As Graham points out... to protect against this, a lead free product would have to be shipped in a heated container... a container sitting in a cold dockyard for a couple of weeks would be enough to start the lead free solder joints to disintegrate.

Sure does seem bad news as far as safety / reliability is concerned and the arguments for unleaded solder don't really convince me..... give me safety and reliability over a few green hippies legislating against anything that offends them anyday.

 

[chillysalsa]

The failure to recycle used PCBs (especially those from electronics that are out of date every 3 years like computers!) is the real issue I believe. There's a concern if it getting dumped into land-fills that can contaminate the local watersupply.

 

[PinkFloyd]

Quote:

Originally Posted by chillysalsa The failure to recycle used PCBs (especially those from electronics that are out of date every 3 years like computers!) is the real issue I believe. There's a concern if it getting dumped into land-fills that can contaminate the local watersupply.

Our water was "delivered" to our homes through lead pipes since the Roman times.. it's only in recent years they have got round to replacing the lead pipes in favour of plastic ones.. people are living longer these days and todays 100 year olds probably consumed water from lead pipes for 90 of those years.

 

[drewd]

Quote:

Originally Posted by PinkFloyd lead comes out of the earth in the first place, it's not man made. Also, there are 600 million homes in Europe that have lead flashing on their roofs so everytime it rains lead finds its way into the water system.

True, lead is a natural element, but the problem that the law is trying to address is where the lead goes after it is mined, refined, used and discarded. Once it's out of the ground, you can't really rely on the "natural element" argument. We've moved it from the mine to a new environment.

While I'm not an environmental expert, I do have some experience with lead-free solder in industrial applications. The company that I work for uses solder by the truckload to assemble PCBs. We've been working with lead-free solder for several years. The alternatives are not just tin/silver...there are quite a few alloys that we're experimenting with that work quite well at the same temperature ranges as traditional tin/lead solder. There are drawbacks to the new alloys, but primarily they involve cost. Tin/lead is cheap because the material is plentiful and produced in huge quantities. Lead-free solder alloys are new and produced in substantially smaller quantities.

I agree that if 97% tin was the only alternative to tin/lead that we'd have a problem on our hands. But it's not the only alternative. The European directive is just the wave of the future. Even without similar legislation in the US and Canada, some of our customers are still requiring lead-free assemblies. We don't have any problem delivering. It's not the disaster that Graham Slee predicts. In fact, the RoHS directive doesn't specify that only 97% tin is the only alloy that can be used. It just mandates the elimination of lead.

-Drew

 

[PinkFloyd]

Quote:

Originally Posted by guzzler The copper/tin solder which is now being introduced will have been tested under -13C, considering the vast majority of semiconductors and parts are specced -40 - 150C. g

Graham has been in touch with Analogue devices and they will "not" be producing lead free semiconductors in anything other than SOIC packages when the new directive comes into force which means he will be forced to either find another manufacturer who can supply an alternative lead free package or use surface mount components.

There's a lot more to all this than meets the eye and industry, public safety and equipment reliability will suffer as a consequence if this crazy directive comes into force.

I've got some of this solder and will put together something like a simple crossfeed circuit and stick it in the deep freeze for a couple of weeks..... it would be interesting to see just how long the joints lasted compared to leaded solder

 

[PinkFloyd]

Quote:

Originally Posted by drewd I agree that if 97% tin was the only alternative to tin/lead that we'd have a problem on our hands. In fact, the RoHS directive doesn't specify that only 97% tin is the only alloy that can be used. It just mandates the elimination of lead. -Drew

Agreed,

But how many manufacturers are going to use more expensive solder? Tin is the cheapest so will be the most commonly used type of solder.. we're not just talking audiophile circuits here Drew, we are talking across the board so the "cheapest" solder will be the solder of choice and that means 97% "tin"

 

[drewd]

Quote:

Originally Posted by PinkFloyd Agreed, But how many manufacturers are going to use more expensive solder? Tin is the cheapest so will be the most commonly used type of solder.. we're not just talking audiophile circuits here Drew, we are talking across the board so the "cheapest" solder will be the solder of choice and that means 97% "tin"

Well, I wasn't talking audiophile circuits, I was talking general purpose circuit boards. The market that I'm in (not the audio market...my "real" job) is just about as commoditized as any market can be. We deal in cost reductions of fractions of a cent, so for us, 97% tin solder would make economic sense, save for the fact that once our boards started to fail because of poor quality solder, we would lose all of our business. So for our lead-free customers, we use a tin/silver/antimony alloy that is more expensive than tin/lead, and definitely more expensive than tin/silver. It's as robust as tin/lead. Unfortunately, antimony is also quite toxic - but at least it's not nearly as concentrated as the lead was.

Manufacturers will use what their customers demand. If their customers start experiencing failures due to poor solder performance, then the manufacturers will either use better solder or lose business. If a manufacturer continues to use poor quality solder, then I think that it's also safe to assume that they're cutting corners elsewhere. That goes on today, as well - there will always be a market for crappy manufacturing. But for the vast majority of electronic products, lead-free solder isn't going to be a problem.

-Drew

 

[jasonhanjk]

In the current transition phase from leaded to lead-free will definately be problematic. After that will be smooth sailing.

Why would anyone want to believe in unproven theory. Pipes using lead for the past 100 years, c'mon, you expect me to believe that? Steel was the metal that was widely use since 100 years ago when the industrial age began in UK. Why steel? BECAUSE IT IS CHEAPER THAN LEAD!!!

Which nation holds the highest record of longevity? It is Japan. Now guess what they use to transfer water to their home.