British Historic Cannonballs
British Historic Cannonballs
(OP)
Any suggestions on how to keep the cannonballs from corroding on exposure to air?
From the BBC:
The Mary Rose sank in 1545 and was raised from the sea in 1982. The cannonballs on board are difficult to conserve because chlorine has got into them from being in the sea. The chemical has got in all the way to its core. This means that they start to corrode if they are exposed to the air.
Dr Schofield's team has tried to remove the chlorine by soaking some cannonballs in solution. But the researchers found that although they had extracted some they hadn't removed it all. They discovered this when the cannonballs began to disintegrate when they were put on display.
http://www.bbc.com/news/science-environment-433347...
Dik
From the BBC:
The Mary Rose sank in 1545 and was raised from the sea in 1982. The cannonballs on board are difficult to conserve because chlorine has got into them from being in the sea. The chemical has got in all the way to its core. This means that they start to corrode if they are exposed to the air.
Dr Schofield's team has tried to remove the chlorine by soaking some cannonballs in solution. But the researchers found that although they had extracted some they hadn't removed it all. They discovered this when the cannonballs began to disintegrate when they were put on display.
http://www.bbc.com/news/science-environment-433347...
Dik





RE: British Historic Cannonballs
Hunley
RE: British Historic Cannonballs
To paraphrase Monty Python, this is an ex-cannonball.
"Everyone is entitled to their own opinions, but they are not entitled to their own facts."
RE: British Historic Cannonballs
Dik
RE: British Historic Cannonballs
Sent your info on to the MaryRose.org
Ironic metallurgist:
Sent your info on to John Cleese
thanks... Dik
RE: British Historic Cannonballs
RE: British Historic Cannonballs
Should have replied... thanks for the info... have passed it on, too.
Dik
RE: British Historic Cannonballs
what about coating with resin ?
RE: British Historic Cannonballs
Sent the information about displaying them in a fluid and added the suggestion of a coating system... heard nothing back from them. From the photos of the deteriorated cannonballs, I would never have guessed that they would have deteriorated like that...
Dik
RE: British Historic Cannonballs
That is generally what is typically done, to maintain the item in storage until the item undergoes conservation.
Problem with this solution is that exhibit visitors want to see the real thing. You could also show images of the item too, but exhibit visitors want to see the real thing.
RE: British Historic Cannonballs
The fact that these are intact as found and only crumble on exposure to air tells me that it is the oxidation of the internal phases that are driving the destruction.
Perhaps an applied electrical current while submerged in hot water would be a way to 'de-tox' these.
I presume that a sample has been core drilled from one for detailed chemical and structural analysis?
Sounds like a job for someone working on a PhD in electrochemistry.
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P.E. Metallurgy, Plymouth Tube
RE: British Historic Cannonballs
Will pass that info on...