I bought zinc powder, but most arent powder, they'er large pieces. Why???XeonTheMGPony - 24-7-2019 at 03:12
Usually it is a granular powder, reason is oxidation, Super fine dusts oxidize super fast.TmNhRhMgBrSe - 24-7-2019 at 03:32
I tried pressing with spatula to break them but they're reallu hard, not because stick by water. I also tried adding the pieces to acid and hydrogen
formed.TmNhRhMgBrSe - 24-7-2019 at 03:51
But what's the relationship between powder and oxidation, XeonTheMGPony?Pumukli - 24-7-2019 at 05:05
Powder = big surface area = fast oxidation.
My zinc powder also contains bigger "chunks" and very fine powder particles. I think the "what you pay for is what you get" applies here.
With a fine sieve these powders could be improved. Unfortunately such sieves are not cheap.
Ball milling may help too, but I'm not sure if there were any particular do-s and dont-s regarding ball milling zinc to fine dust.Amos - 24-7-2019 at 05:13
Maybe take a fine kitchen seive and separate dust and granules to use for separate projects? It's not the end of the world.TmNhRhMgBrSe - 24-7-2019 at 08:03
Pumukli, but why there are chunks? Why don't the manufacturer powderise all chunks before selling?
[Edited on 19-7-24 by CELamCheng]
[Edited on 19-7-24 by CELamCheng]TmNhRhMgBrSe - 24-7-2019 at 08:14
I tried used a pliers to press the chunks. They break. Why? Shouldn't they become thinner pieces?stygian - 24-7-2019 at 08:17
"is zinc malleable" - "Zinc is a bluish-white metal with a shiny surface. It is neither ductile nor malleable at room temperature."Tsjerk - 24-7-2019 at 09:47
Why don't the manufacturer powderise all chunks before selling?
As stated before: Because you didn't pay them to do so. RedDwarf - 24-7-2019 at 09:53
What are you trying/planning to do with the zinc? For some uses you really don't want powder and turnings or chunks are much better.Tsjerk - 24-7-2019 at 10:14
I did some organic reductions and it was a pain to keep it cool with the powder I had, but chunks I would imaging would also be a pain as they are
harder to stir.
For reductions I would go for the chunky stuff after sieving, for pyrotechnics I would go for the quality powdered stuff SWIM - 24-7-2019 at 10:53
What you're describing sounds kinda like mossy zinc.
It's mostly rounded lumps that have a large surface area due to the way they're made. I believe they are slightly porous.
They vary in size from quite small to several times the size of a peppercorn.
Could it be some of that mis-labeled?MrHomeScientist - 24-7-2019 at 11:39
No, my zinc powder has the same thing. Mossy zinc is pretty distinct and quite different.
I suspect the chunks are powder that got fused together during packaging or storage. The powder at the bottom of the barrel would be pressed together
by the weight of everything above it, and a soft metal like zinc might "cold sinter" together into lumps. That's the theory, anyway.Abromination - 24-7-2019 at 15:57
"is zinc malleable" - "Zinc is a bluish-white metal with a shiny surface. It is neither ductile nor malleable at room temperature."
I would like to disagree on the malleability statement. Although quite brittle at ST&P, you will still find zinc decently malleable. It still will
bend and can be pounded at least a bit before cracking.
It is also not common to see the true color of zinc as it instantly oxidizes instantly on contact with air.
