First major foul up!! what a mess..need help on this one

[ilikesilver]

Well, i was doing great on my foils, they are doing well, got all my mash in one pot, now i have to find a good dish to boil them down tomorrow and weigh them out. but thats NOT what i screwed up, few.

As i was cleaning out all my boards about 7 a.m. this morning, i noticed that my new fangled AP bucket looked awfully lonely, so i decided to bust up all my ceramic chip chips, which was about thirty of them, decided against having a collection, dont have the room. So i took a small metal bucket and a hammer and procceded to bust them all up, then i poured them into the AP bucket, i loosely covered it, and put a block of wood on it so it could breath a little and left it next to my shed. Well i went to mother inlaws to open her pool for the season and a BBQ, that was good, burgers, dogs, chicken, salads, fat and happy tonight, till i got home that is. It was starting to get dark out and went out to my shed and check the bucket and agitate it some, when pulled out the inner bucket, uuuuugggg, what a mess, big chuncks of what looks like a copper colored mess on everything, and there was fizzing quite violently in the bucket. I took the whole inner bucket out and put into a fresh bucket of water and rinsed really well. Then i rinsed again, the water is discolored badly, like a grey, but whats interesting is that the original AP fluid is green. I started separating everything and found out what i did. Slap me now,, when i busted up all the ceramic cpu's i neglected to take out the bright silver tops off of 8 of the cpu's. What is this stuff, because it dont like AP at all and it made quite a mess. Copper chloride im thinking. help me out guys and what do i do next. tim

 

[lazersteve]

The thin square foil on the top of the ceramic cpu is Aluminum. They react violently with HCl and will cement copper as a moss form solution.

Steve

 

[ilikesilver]

The thin square foil on the top of the ceramic cpu is Aluminum. They react violently with HCl and will cement copper as a moss form solution.

Steve

so steve, is the batch bad now, or can i just separate it all out and start with a new batch of HCl ? or is the original fluid still good, do i just need to add some more muratic acid? tim

 

[Geo]

too, the legs (which are Kovar) would have cemented the copper out of solution. add the correct amount of HCl to finish the job and continue the dissolution of the base metal. keep this in mind for the next time, once you start a process, stay with that same process till the end. definitely until you have more experience.

and too, keep in mind that theres only so much iron you can dissolve with AP before the solution stops dissolving metal at all.

 

[ilikesilver]

too, the legs (which are Kovar) would have cemented the copper out of solution. add the correct amount of HCl to finish the job and continue the dissolution of the base metal. keep this in mind for the next time, once you start a process, stay with that same process till the end. definitely until you have more experience.

and too, keep in mind that theres only so much iron you can dissolve with AP before the solution stops dissolving metal at all.

surprisingly a lot of the legs didnt get touched, they still look new, but i thought that kovar was a base metal in cpus that were not ceramic, but in the fiber ones, so apparently that is not true. So Geo, should i use the original AP fluid mix and just at some more muratic acid, or start a new batch and move everything over to that and just keep out all the aluminum caps? I also noticed that after removing all the chips from the fluid, the hole bottom of the bucket is full of a black looking sedament. did it desolve gold, or is that from the aluminum? tim

 

[bswartzwelder]

Question...Why would you add chips to AP? It might get rid of some of the metals, but the gold in the chips should remain untouched. Just wondering.

 

[Geo]

i process fiber CPU's in AP all the time, it cuts back on the hassle of dealing with iron in your AR process. all packages that have silicon chips and legs that either plug in or are soldered in will have Kovar base metal. it was specially designed just for the purpose because it does not expand and shrink due to being heated and cooled like other base metals. its not only ceramics that it is used for even though thats what it was designed for. if you use AP to digest these base metals, just be aware that its useful life will be shortened by adding iron and nickel. keep this solution separate for use with CPU's and chips. after the solution stops reacting while cool, you can heat it and add a little fresh hcl and bubble air through it and the color will change to a reddish tint. you can then use this solution to strip fingers quickly. you have changed Ferrous chloride (iron(II) chloride) to ferric chloride (iron(III) chloride). this solution can only be used once or until the action stops, then it needs to be treated and disposed of.

the fact that most of the legs had not been reacted upon is a good sign, the gold plating is still intact and hasnt been scratched off due to wear and tear. all thats happened is the iron sucked all the copper from solution. add some fresh hcl and an air supply and let the dissolution continue. let the solution turn completely black before you change the solution.

 

[bswartzwelder]

Geo,

THANK YOU. I didn't realize AP could help with ceramic chips. It was my understanding they shouldn't be incinerated due to the toxicity of the gasses given off and AR would not be a method of choice. Have not heard of AP on these chips before, so this is a new way to deal with them for me. The more I read on this forum, the more I learn from it.