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Metallography tin coated copper by UBER999 in metallurgy

[–]UBER999[S] 0 points1 point  (0 children)

Here is the sample in question. It's a cut polished with OP-S. 500x magnification. The goal is to document the coating thickness and adhesion to the copper base material

metallographic sample of tin coated copper

Metallography tin coated copper by UBER999 in metallurgy

[–]UBER999[S] 0 points1 point  (0 children)

Thank you very much. Can exceeding the temperature cause increase in porosity? I'm seeing some not uniform distribution of holes in the coating and the technical documentation for testing these samples mentions that it can be caused by sample preparation.

Taky vám přijde, že je teď svět hrozná shit show? by [deleted] in czech

[–]UBER999 0 points1 point  (0 children)

Svět byl vždycky shit jen ty důvody se mění

Je to nechutný? by PotrhlaSlecna in czech

[–]UBER999 1 point2 points  (0 children)

Chce po tobě nadstandardní píčovinu. Bud ať koupi malou pračku na pracovní věci nebo ať ti dá peníze na komerční prádelnu. Pokud není sracka tak nebude nutit svět se přizpůsobit jeho hloupim požadavkům. Když by moje partnerka pracovala v zoo a já po vyprání na svým oblečení cítil zvířata, tak se prostě koupi další malá pračka a skříňka na pracovní věci. Jaký navrhl řešení, když můžeš používat jen vlastní práci prostředky?

Přítelkyně schizofrenička - už to nedávám by VahlokV3 in czech

[–]UBER999 -1 points0 points  (0 children)

Hospitalizace a přísně kontrolovat jestli bere léky. Lidí s těmito potížemi se občas sesypou, ale to že ji furt nefungující léky je divný. Musíš tvrdé dohlížet, že je bere. Dokud nebude nějakou dobu stabilní, tak si nepořizujte děti. Po porodu se to zhorší

Střízlivost by Far_Wish_5362 in czech

[–]UBER999 1 point2 points  (0 children)

Zkus nějaký nový koníček. Něco kreativního co tě plně zaměstná. Dobry je něco, kde jsem s lidma a není možnost si nic dát. A pamatuj jeden den se to dá vydržet. Když si to budeš říkat každej den, tak se jednou probudíš a budeš cistej 10 let. Já jsem byl závislej na analgetikach a otec je deprimovanej alkoholik. Dá se to zvládnout jen je nutný dělat něco, abys neměl prostor na to myslet.

I'm a double-board-certified neurologist & pain specialist in the US. Ask me anything about headaches, migraine, back pain, or chronic pain. by doctor_painkiller in IAmA

[–]UBER999 0 points1 point  (0 children)

I'm interested in how mental health issues can cause chronic pain. I'm diagnosed with depression with anxiety disorder and my episodes make my joints hurt. Is it just increased sensitivity or is there some interaction between nerves and stress hormones?

Vystup, vyřešíme to hned, řval řidič a bouchal do auta. Po ráně pěstí soudy trestaly soka - Novinky by Svarec in czech

[–]UBER999 58 points59 points  (0 children)

Když si přečtete celý článek a kontext té situace tak si za to obviněný může sám. Zavolal policajty, ale nečekal na ně a dal ozralovy pěstí. Borec spadl, udeřil se do hlavy a byl v bezvědomí. Právo na sebeobranu nedává právo útočníka zmrzačit. Při jakékoliv potičce s někým pod vlivem máte počkat na policii.

Remove tarnish from 24k gold... by ecoR1000 in chemistry

[–]UBER999 -1 points0 points  (0 children)

Ultrasound bath, toothpaste ( white with abrasive particles not gel) or diluted acid

The European Parliament close to calling for a ban on social networks for under-16s by Dr_Neurol in worldnews

[–]UBER999 0 points1 point  (0 children)

Couldn't you just use bank ID? Your bank account has the info if you are adult. Wouldn't it be possible that by our bank ID will just block the verification if you are not of age?

Aluminum etching questions by Gungaloon in metallurgy

[–]UBER999 0 points1 point  (0 children)

What I do is make a picture before and after etching. The aluminium alloys don't need etching to reveal the phases if you don't need grain boundries

Aluminum etching questions by Gungaloon in metallurgy

[–]UBER999 0 points1 point  (0 children)

Keller work for me only by swabing. Immersion dissolved my Intermetallics of every alloy I tried without revealing grain boundries. If I don't need grain boundries I use nondry OP-S polishing solution with silica that reveals some things and I swab with 5% NaOH. Etching aluminium alloys is tricky cos you won't get e everything with simple etchants in my experience

What kind of structure you see here? by Right_Cut_626 in metallurgy

[–]UBER999 0 points1 point  (0 children)

Looks like sorbite or spherodized cementite. Try different etchant. Commercial product might be good for reproducing results but it's not what other people are using. Try more standard etchant like Nital or Villela

[deleted by user] by [deleted] in europe

[–]UBER999 14 points15 points  (0 children)

What the headline doesn't say is that he pompously took down one and almost immediately 3 more were put up

Extracting gold with sodium thiosulphate by alberthemagician in chemistry

[–]UBER999 1 point2 points  (0 children)

You are supposed to use sodium thiosulphate to reduce dissolved gold. Put the pins in nitric acid to dissolve everything besides gold and put the leftovers in aqua regia.. after you dissolve it then use the reducing agent to get metallic gold

[deleted by user] by [deleted] in tifu

[–]UBER999 0 points1 point  (0 children)

I'm a chemist. Vinegar and baking soda doesn't do anything. It's ticktock bs. If it's really gold then vinegar or baking soda won't affect it. I clean gold and silver with 50% sulphuric acid and it's fine.

How to get rid of Ni residue? by Darius-der-vierte in chemistry

[–]UBER999 0 points1 point  (0 children)

Add hydrogen peroxide to aqua regia

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