It's still nichrome. Different mixtures of the nickel and chromium plus other additives give different resistance factors. The one you referenced is Nichrome 60 which is only one of many different formulations. Try looking here. Go to bottom of pasge as they give listing of different formulations with resistance per foot and the mixtures.
"Corrodes easily" is an understatement once you start heating it up. (Try running a bulb without an envelope... he, he!)
But there is a new and better reason to avoid tungsten: It is *extremely* carcinogenic. A tiny fleck stuck in your skin can cause cancer. (Well, it does in lab animals. If any creationists out there don't think they share any common ancestry with rats and mice, by all means go ahead and experiment on yourself to provide some data points for humans.)
Best regards,
Bob Masta D A Q A R T A Data AcQuisition And Real-Time Analysis
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Cor strewth!. Had me worried there, with the amount of Tungsten Carbide tooling I use. Looked on the web and could not find any carcinogeneic effects for Tungsten.
You're weren't by any chance thinking of depleted Uranium, Tungsten penetrators by any chance?
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Hi, Jon. If you're looking for a small quantity of good resistance wire, you could do a lot worse than just scrounging a power wirewound resistor with ceramic coating, and carefully chipping off the outer coating. If it hasn't cracked by the time you're done, break the ceramic core and voilla! resistance wire with pre-welded contacts that you can solder (the caps and leads).
This has the added advantage of being low temperature coefficient wire (resistance changes with heat, and standard heater wire will vary by a lot more than the 5% tolerance of resistance wire nichrome alloy). Make sure you derate the wattage a lot -- the coating and ceramic core really help dissipate the heat, and with them gone, it can't handle the same wattage.
Tungsten powder is used as a filler material in thermoplastic composites which are used as a nontoxic substitute for lead, in bullets, shot, and radiation shields.
Tungsten is also beginning to see uses in jewelry. Its hardness makes it ideal for rings that will never scratch, and will in turn not need polishing (this is especially good for brushed designs).
On August 20, 2002, officials representing the U.S.-based Centers for Disease Control and Prevention announced that urine tests on leukemia patient families and control group families in the Fallon, Nevada area had shown elevated levels of the metal tungsten in the bodies of both groups. Sixteen recent cases of cancer in children were discovered in the Fallon area which has now been identified as a cancer cluster, (it should be noted, however, that the majority of the cancer victims are not long time residents of Fallon). Dr. Carol H. Rubin, a branch chief at the CDC, said data demonstrating a link between tungsten and leukemia is not available at present.
Nope, tungsten slivers. Saw it in Science News last year. A search on "Tungsten Cancer" turns up several hits, including:
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Just dredged up the original Science News article from my dead-tree archives: The tests were on an alloy that was 91 percent tungsten, with cobalt and nickel, commonly used in bullets as a replacement for uranium and/or lead. Pellets were surgically implanted in rat leg muscles. Some groups of rats got other metals (nickel or tantalum). Within 5 months, all animals getting tungsten were dead from cancer that had spread to their lungs. Tantalum caused no problems; nickel caused fatal cancers at the wound sites, but did not spread to the lungs. The findings were to be reported in "Environmental Health Perspectives". Research was conducted by John F. Kalinich at the Armed Forces Radiology Research Institute in Bethesda, MD.
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Bob Masta D A Q A R T A Data AcQuisition And Real-Time Analysis
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Yes. When searching I turned up that Tugsten-alloy study in numerous places and it's extremely worrying.
But ... I should be worried but I'm not. Why? ...Simply because no other research group seems to have picked up on it. This is very puzzling as the Rat cancers reported in at 100% and not the usual wishy-washy "we've found a statistically significant correlation". For sure though, a vast army of other researchers would have seen this study. Seen it's Black and White outcome and dreamed pleasant dreams of big grants, seminal papers, fame and fortune, all built on the back of telling the world of this new Satan in our midst. They've now had over two years and zilch!. I'd like to think that because of the universal use of Tungsten, there's been a world-wide cover up. Sadly, I suspect the real 'truth' is much more mundane.
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On Sat, 05 May 2007 12:54:21 +0000, Bob Masta wrote: ...
Feh.
EVERYTHING causes cancer in lab animals. That's the way they breed them, to be predisposed to cancer, so that they have a handy supply to justify the huge grants they get when they show that some advocacy group's favorite evil substance "causes" cancer.
ISTR a lab which tested the surface of grilled steaks and found that it caused cancer. When asked what happened to the steaks the researchers replied that they ate them.
In looking at the original report, it seems to me that another possible interpretation of the data would be that nickel caused the cancers and tungsten caused them to spread. They didn't test pure tungsten, only alloyed with nickel and cobalt. Since nickel alone caused non-spreading tumors, maybe the combination with tungsten caused some second-order effect that simply increased the ability to spread. Angiogenisis could increase blood contact with the tumor, for example. Or maybe the tungsten prevented the tumors from consolidating, leaving them as lots of loose, mobile cells. Lots of alternatives.
But personally, I'm still not planning to do any more messing around with tungsten wire. The stuff is extremely brittle and unworkable in the first place, and even when you simply cut it with (heavy duty) side cutters, it tends to splinter at the cut. (The wire is ostensibly solid, but at the cut/broken end you can see 3 separate strands that appear to have been milled together to make the final product.)
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Bob Masta D A Q A R T A Data AcQuisition And Real-Time Analysis
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