Pot dichromate

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biffo
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Pot dichromate

Post by biffo »

Hi guys please can you tell me what is the purpose of pot dichromate is in the formula,does it protect the MgAl or something else. Ap 56 MgAl 200-325# MgAl 325#19·6 /3·7 barium sulphate 14 pot dichromate 4·7 vasaline 2 . Many thanks B the above is a strobe rocket composition.
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Lloyd
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Re: Pot dichromate

Post by Lloyd »

Biffo, I know the potassium dichromate will help protect magnalium, because I use it for just that. But four-point-seven percent is A LOT!!!

For just protection, I'd use something about 0.5-1.0%. My guess is that they're also using it as a catalyst (in which duty it can serve).

Lloyd
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Fulmen
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Re: Pot dichromate

Post by Fulmen »

It's also an oxidizer. So whatever the reason was it will probably have a real impact on performance. It's not a nice substance, so you won't find it in any modern composition unless it's really needed.
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Pyro-Gear
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Re: Pot dichromate

Post by Pyro-Gear »

Biff, all the strobe formulas I have called for 4.7-5% dichromate.

I don’t know of any other (reliable) formulas that don’t use dichromate, drop me a line if you need some buddy.
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richardh08
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Re: Pot dichromate

Post by richardh08 »

Apart from its role in protecting Mg or MgAl in mixtures that also contain AP, it is said by many that it improves the quality of the strobe flashes. One of the results of Corbel's study was that including K2Cr2O7 slightly altered the frequency, but also made the flashes sharper and more regular.
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biffo
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Re: Pot dichromate

Post by biffo »

Thanks gentleman I need to read up on this chemical .B
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biffo
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Re: Pot dichromate

Post by biffo »

Hi gents if one was to work with this unsavoury chemical apart from the obvious immaculate housekeeping,masks gloves goggles work outside wash etc have you any tips /advice for anyone not familiar with its shocking msds. Thanks B
Pyro
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Re: Pot dichromate

Post by Pyro »

Don't worry, just avoid breathing the dust and try to avoid skin contact.

Clean your working area, change working clothes if it was really dusty and take a shower afterwards.
davidg
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Re: Pot dichromate

Post by davidg »

If there is a chance of skin contact,apply a barrier cream to any exposed skin first. I used this stuff in fifteen kilo lots in the bad old days with acetic acid. No matter how careful we were,there was always a small chance of exposure. We used it to oxidize sulphur black and navy dyes. If the dyestuffs,alkali and ancillaries didn't get you,the oxidation chemicals would. Ah the wonderful old days
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