Tantalum Foil Drawing Cracks after First Operation
Tantalum Foil Drawing Cracks after First Operation
(OP)
Hi Colleagues,
Recent tantalum .002" foil material (either e-beam melted or arc cast) has tearing problems forming small cup shapes, while 5-10 years old vintage material (.0023 to .0024" thick) does not. The source of the old vintage material cannot be verified, but we can can assume that both materials came from the same supplier. Recent material is slightly harder than the older material (120 KHN vs 90-100 KHN). We tried to anneal the material once and even twice without any improvement.
Has anyone ever run into this problem?
Any suggestions on sources for high purity Ta foil?
Thank you.
Recent tantalum .002" foil material (either e-beam melted or arc cast) has tearing problems forming small cup shapes, while 5-10 years old vintage material (.0023 to .0024" thick) does not. The source of the old vintage material cannot be verified, but we can can assume that both materials came from the same supplier. Recent material is slightly harder than the older material (120 KHN vs 90-100 KHN). We tried to anneal the material once and even twice without any improvement.
Has anyone ever run into this problem?
Any suggestions on sources for high purity Ta foil?
Thank you.





RE: Tantalum Foil Drawing Cracks after First Operation
If Scarrot is no onger operating, one of the priciples was a man by the name of Robert Fairbanks, now retired. Bob was an associate of mine and a very sharp metallurgist. He might still be an ASM member even though retired and maybe could be contacted via ASM if a member.
RE: Tantalum Foil Drawing Cracks after First Operation
RE: Tantalum Foil Drawing Cracks after First Operation
http://www.tantalum-coating.com/index.htm
One thing I remember is that working on making extrusion jets for synthetic fiber we had some problems when we changed the die material. The problem was solved by using a lubricant where we hadn't before. A totally different lubricant was needed when we perforated the formed Ta. There were some discussion at the time about the behaviour of Ta in contact with other metals.
RE: Tantalum Foil Drawing Cracks after First Operation
Sorry it was late and I was tired lasst nite so did not think to Google it until I read btrueblood's comment.