Nickel silver

Model Railroader General Discussion (Model Railroader)
21

If I may clarify a point - it’s been said that one of the advantages of nickel silver is that its oxide will conduct electricity. Yes, it will. Badly, though. Usually this is in comparison to the oxide of brass, which is practically non-conductive.

Nickel Silver is not an alloy of brass just because they share elements. Brass is a final product. Nickel silver is a final product. One does not make brass, then add nickel to make NS.

BTW - U.S. Government bronze spec. G is a composed of 88% copper, 10% tin, and 2% zinc. U.S. Government bronze spec. H is composed of 83% copper, 14% tin, 3% zinc, and 0.8% phosphorus.

22

know of 2 shops withing 40 miles that have used brass track. One has big produce boxes of it sorted into curves, straights, and TOs. http://www.greatesthobby.com/wgh/directory/hobbyshops_info.asp?recid=1955&type=3&mode=view links to their ad at World Greatest Hobbies. Fred

23

A lot of guys using n/s outdoors don’t like it because the coating it gets doesn’t conduct electricity very well, unlike the reply(s) stated earlier.

In fact, I became disapppointed using n/s outdoors (O scale code 148) because of conductivity issues. In fact, I took my multimeter outside and did an Ohms test and didn’t get a signal in most places I tested, with the leads about 15 inches apart. Of course I could clean my track at each session but I didn’t want to go thru with that so I converted my locos to R/C and now the buildup on the rails actually helps provide traction.

Of course 99.999% of you are running indoors so less frequent cleanings would be needed.

On the plus side of things, the rail heads look prototypical in n/s and soldering is a breeze.

Here’s some photos…

24

If you’re building a MoW scene, or you want some rail for flatcar/gondola loads, brass is the way to go. It can usually be bought for next to nothing (about 25 cents a piece here), and since no trains will be running on it, the oxide issue doesn’t matter.

25

It is correct as far as the English language goes, but imprecise. There is a difference. One cannot debunk a myth with vague definitions. As others have already pointed out, an alloy of copper, zinc, and nickel can be many things depending on the proportions, impurities, and how it is processed. An English dictionary is acccurate if one wants to know about pronunciation, parts of speech (adverbs, verbs, nouns), transitivity, plural forms, etc. They are very limited in space so scientifically accurate definitions are very difficult. There are also dictionaries made for various grade levels. I was proof reading for my boss and caught him using definitions out of a grade school level dictionary because it was the “free” on-line one. I hooked him up with a Collegiate level Dictionary to keep him from sounding foolish.

A metalurgy or chemical dictionary would probably have the accurate definitions for this case. Some thing more like this:
http://www.amazon.com/gp/product/0471387355/102-1071854-2491358?v=glance&n=283155

26

Jeffrey, there IS brass in Nickel Silver.

http://www.ballardbrass.com/nominal-chemical-composition.html

27

No, they do not make brass and then add nickel to it and make NS. Once you’ve made brass, it’s brass. Looking at the website you cite - brass has far more (24%-29%) zinc in it than NS has (2%-8%). How are you going to make brass, add nickel, and then lower the zinc content? More importantly, why would anyone even try? Just make NS the first time…

A minor distinction, but a distinction nonetheless.

28

By adding more copper and adding more nickel, you decrease proportionally the zinc content.

I used to work with a metal recycling firm. You CAN take discarded brass, smelt it down, chemically determine its metallurgical content, and add more things to it to create some other alloy, including nickel silver.

Is the final alloy made from recycled metals the same quality as an alloy formulated from the outset? That’s debatable, but that’s another discussion.

29

From http://www.matweb.com

MatWeb, The Online Materials Database
Nickel silver 65-10, UNS C74500

Subcategory: Copper Alloy; Metal; Nonferrous Metal

Key Words: NS103, ISO CuNi10Zn27, CEN CW401J

Component Wt. %

Cu 63.5 - 68.5
Fe Max 0.25
Mn Max 0.5
Ni 9 - 11
Other Max 0.5
Pb Max 0.1
Zn 25

Material Notes:
Excellent corrosion resistance. Excellent cold workability. Fabricated by blanking, drawing, etching, forming and bending, heading and upsetting, roll threading and knurling, shearing, spinning, squeezing, stamping and swaging.

Applications: rivets, screws, slide fasteners, optical parts, etching stock, hollow ware, nameplates, platers’ bars.

Available as flat products and wire.

Physical Properties Metric English Comments

Density 8.69 g/cc 0.314 lb/in³ at 20°C (68°F)

Mechanical Properties

Tensile Strength, Ultimate 338 - 896 MPa 49000 - 130000 psi
Tensile Strength, Yield 124 - 524 MPa 18000 - 76000 psi Depending on temper
Elongation at Break 50 % 50 % in 25.4 mm.
Modulus of Elasticity 120 GPa 17400 ksi
Poisson’s Ratio 0.3 0.3 Calculated
Machinability 20 % 20 % UNS C36000 (free-cutting brass) = 100%
Shear Modulus 46 GPa 6670 ksi

Thermal Properties

CTE, linear 250°C 16.4 µm/m-°C 9.11 µin/in-°F from 20-300°C (68-570°F)
Thermal Conductivity 45 W/m-K 312 BTU-in/hr-ft²-°F at 20°C (68°F)
Melting Point Max 1020 °C Max 1870 °F Liquidus
Liquidus 1020 °C 1870 °F

30

Need to be careful since brass is defined as an alloy of copper and zinc, so indeed nickel silver could correctly be called an alloy of brass with nickel added. Maybe the poster who said tin just mistyped or whatever too. [?] BTW, copper and tin form bronze. Fred

31

Reach into your pocket. Pull out a nickel. Do you see rust? duh. One day schools are gonna actually teach people stuff.
Stephen

32

You’re right - the recycled brass angle never occured to me. I was thinking of virgin brass and NS.