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Ted Mooney, P.E. RET
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Hard Material that is not attacked by piranha and HF
Does anyone recommend a hard and tough ceramic or metal that is not attacked by HF and piranha solution
Punit KohliSouthern Illinois University - Carbondale, IL, USA
October 13, 2008
I don't know what does piranha solution mean. Among metals, either Iridium or Rhodium can be electroplated hard (around 600VHN) and both will resist hydrofluoric acid. High alumina ceramics(99%+) is much harder (2000VHN) and resists hydrofluoric acid.
Guillermo MarrufoMonterrey, NL, Mexico
October 17, 2008
There is a comprehensive Wikipedia article on Piranha solution which came up on top of the list when I simply googled "piranha solution".
Sounds particularly nasty stuff - mixture of concentrated sulfuric acid and concentrated hydrogen peroxide! No doubt named because it voraciously eats any bio substances.
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Bill Reynolds [deceased]
consultant metallurgist - Ballarat, Victoria, Australia
We sadly relate the news that Bill passed away on Jan. 29, 2010.
October 23, 2008
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