Recent content by Matcon

Alternatively, a rectangle to which a right-angled triangle is added and a smaller one subtracted. I did it with trig: quite straightforward

Us it feasible to use what I believe is called an Easy Out? That's a tapered tapping die with a left-hand thread.

Many years ago (>30), plasma-sprayed zirconia was touted as a material for internal combustion engines. At first blush, that should meet operational requirements. I'm no longer up to date with progress in that technology but there is most likely something better in the same field

For removing sprues and vents, surely a wire diamond saw, such as those used for slicing semiconductors, is worth considering? They are designed to avoid surface damage on brittle materials

If pourable and longevity are important, may I suggest that you take another look at silicone elastomers? I am guessing from your application description that you are looking for about a Shore 30A hardness, that has a typical elongation to breakage of 300%. You can get silicone in anything from...

I don't have the reference to hand, but I read recently that you can create fluorescent nanodots of carbon nitride derived from pyrolysis of citrazinic acid. Nominally, that would be hexagonal rings of alternating carbon and nitrogen atoms. If I had to try this, I would be looking at conditions...

There are quite a few so-called NAtural Deep Eutectic Solvents, or NADES, consisting partially or completely of carboxylic acids mentioned in the literature: https://ifst.onlinelibrary.wiley.com/doi/abs/10.1111/ijfs.14013...

Vinegar will promote verdigris corrosion if you leave it in place. Wash the vinegar off when the item is clean and dip in a weak alkaline solution to make sure there's nothing left in the crevices

There are a couple of alternative approaches to consider, that I may be able to expand upon later. Just on principle, I would experiment on copper coupons before trying unfamiliar chemistry. There are two detailed articles about making and characterising verdigris...

That mixture works especially well when you include sodium chloride. Apart from being a mild abrasive, copper forms a soluble complex ion with chlorine. Most versions I have seen are salt and vinegar, applied with a Q-tip

Fundamentally, Young's Modulus is largely determined by intermolecular forces. At equilibrium, atoms sit (or, more correctly vibrate around) a point a certain distance from their nearest neighbours at which potential energy is minimised. You can think of it as sitting at the bottom of an energy...

Here's a wrinkle on creating magnetite coatings from marine archeologists: https://www.jstor.org/stable/1506066?seq=1 They give you solution compositions and methods

One of these, perhaps? picked up in a Google search 6 gms selenic acid 10 gms copper sulphate 4-6 ml nitric acid(1,34 gm/cm3) 1 lit water 20-25 °C temp. tannic acid ...20 gm tartaric acid...20 gm water.....1 lit The first method displaces copper from solution and converts it to black copper...

Agreed. Surely the approach is to specify the properties and find which materials fit those properties rather than specify the material and figure out how to modify it to meet requirements? If you know your materials science, you should be able to work out the microstructure/s that will attain...

I don't think there are any practical examples of this happening. With noble metals, like silver, gold etc, the oxide decomposes at temperatures below the melting point of the metal. For a metal oxide to dissolve, the metal-oxygen bond strength would need to be close to the metal-metal bond...