german spreaker?

A jiffy bag full of the stuff will be on its way to you tomorrow.

Letting people who might benefit from its services know it exists will be quite sufficient. REMAP is rather an old fashioned charity in that it doesn't spend its donations on fund raising and publicity so lack of awareness of its existence is always an issue.

Time and skill are the biggest and by far the most important donations we get from panel members. If you can spare either then your local panel would welcome your involvement :-).

We have one young lady (age 8) locally who our local Panel has constructed various devices for who has a character inversely proportional to her restricted size. Watching her most effective supervision of a bunch of retired engineers making things for her is quite illuminating!

Arrived safely, and thank you.

First impressions - doesn't look or feel like Nichrome, at least it is not the traditional 80% nickel 20% chromium Nichrome, 90/10, or Nichrome A. There are a slew of alloys with Nichrome in the name these days, but I doubt it is any of those either.

Looks like it has a good proportion of nickel and chromium in it though.

Diameter is pretty uniform, 0.696 to 0.699 mm. A 1.018 m length weighs 3.104 grams.

[] -> Specific gravity is 7.97 +/- 0.05.

(80/20 Nichrome is 8.41, "A" is about 8.4, some of the other nichromes go down to about 8.2. Below 8.2 and it pretty much has to have a good bit of iron in it. Stainless is usually about 8.02, within the range).

All this would strongly suggest to me that it is stainless or one of the incoloys, the most common of which is alloy 800 with a SG of 7.98.

Will do some more tests later, my ohmmeter needs a new battery and I don't have time for more complex tests now.

- - - - - - later

Have now done some more tests.

It is not magnetic.

No visible reaction with dilute or fuming nitric acid, aqua regia turns nickel-green and cloudy/gelatinous then brown, liquid gives copious red/brown precipitate with excess NaOH.

Summing up, it contains mostly iron (the red/brown ptte), a good bit of nickel (the green jelly), no cobalt (the green again). Probably some Cr too, to protect the iron and nickel from the acid.

I'm guessing slightly about the nickel as I don't have any ammonia to hand to make sure, and the green could in theory be caused by copper or iron, but the jelly-ness and the exact colour are very 10%-nickelly.

A 38.06 g (equivalent to 12.48 m) length has a resistance of 23.08 ohms at

22.7 C. That's a linear resistance of 1.849 ohms/m. [] -> Bulk resistivity is 0.7075 +/- 0.004 uohm-m.

(Nichromes vary between 1.08 and 1.50 uohm-m, Incoloy 800 is about 0.93, stainless (304/316) is 0.69/0.74 uohm-m).

Conclusions:

It is not Nichrome.

It is most likely a low-300-series stainless, or just possibly one of the

800-series Incoloys*, though not Incoloy 800 itself.

It does feel too soft and look too Ni-rich for a typical stainless, but then they do do unexpected things with stainless wire. Perhaps some moly, manganese and/or exotic additions? From the numbers it could have up to maybe 20% Ni, but not much more.

The 800 series Incoloys are Fe/Ni/Cr alloys, usually with some small quantities of added extras - as are the austenitic stainless steels.