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Author Topic: Questions for people who understand the metal alloys used in the LL nails  (Read 267 times)

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SpeedDialer

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Betz said in his interview with cyborg4life that for a magnetic lengthening nail you need an iron-containing metal

I maybe misunderstood but my (possibly wrong) interpretation of his interview was that:

1. For stryde they tried stainless steel (which does contain some iron) but the problem is that stainless steel on stainless steel caused corrosion (from the paley interview)?

2. But Betzbone 2.0 and G-nail, do they use cobalt chrome alloys that are stronger and have (basically) no corrosion? But cobalt chrome doesn't contain iron so it can't be used for magnetic nails?
'Co-Cr alloy was first discovered by Elwood Haynes in the early 1900s by fusing cobalt and chromium. The alloy was first discovered with many other elements such as tungsten and molybdenum in it. Haynes reported his alloy was capable of resisting oxidation and corrosive fumes and exhibited no visible sign of tarnish even when subjecting the alloy to boiling nitric acid.[2] Under the name Stellite, Co-Cr alloy has been used in various fields where high wear-resistance was needed including aerospace industry,[3] cutlery, bearings, blades, etc.'

3. But what's confusing me is this: precise used titanium or a titanium alloy I thought -> does this contain any iron? Only a little bit it seems? Why didn't precise have as many corrosion issue problems?
"Titanium alloys typically contain traces of aluminum, molybdenum, vanadium, niobium, tantalum, zirconium, manganese, iron, chromium, cobalt, nickel, and copper."

I don't know how they will fix this problem for the next precise/stryde nail. They need an iron-containing metal for the magnetic mechanism no? But iron-containing alloys like stainless steel can sometimes have corrosion when it rubs against itself no? So what then are they screwed or are there other engineering / materials science ways around this problem?
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tallmen

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Re: Questions for people who understand the metal alloys used in the LL nails
« Reply #1 on: November 16, 2022, 05:56:37 AM »

Dr assayag disputed betz claim in one of the comments saying that it also has a corrosion issue.
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Ascender

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Re: Questions for people who understand the metal alloys used in the LL nails
« Reply #2 on: November 16, 2022, 10:02:28 PM »


Betz said in his interview with cyborg4life that for a magnetic lengthening nail you need an iron-containing metal

I maybe misunderstood but my (possibly wrong) interpretation of his interview was that:

1. For stryde they tried stainless steel (which does contain some iron) but the problem is that stainless steel on stainless steel caused corrosion (from the paley interview)?

2. But Betzbone 2.0 and G-nail, do they use cobalt chrome alloys that are stronger and have (basically) no corrosion? But cobalt chrome doesn't contain iron so it can't be used for magnetic nails?
'Co-Cr alloy was first discovered by Elwood Haynes in the early 1900s by fusing cobalt and chromium. The alloy was first discovered with many other elements such as tungsten and molybdenum in it. Haynes reported his alloy was capable of resisting oxidation and corrosive fumes and exhibited no visible sign of tarnish even when subjecting the alloy to boiling nitric acid.[2] Under the name Stellite, Co-Cr alloy has been used in various fields where high wear-resistance was needed including aerospace industry,[3] cutlery, bearings, blades, etc.'

3. But what's confusing me is this: precise used titanium or a titanium alloy I thought -> does this contain any iron? Only a little bit it seems? Why didn't precise have as many corrosion issue problems?
"Titanium alloys typically contain traces of aluminum, molybdenum, vanadium, niobium, tantalum, zirconium, manganese, iron, chromium, cobalt, nickel, and copper."

I don't know how they will fix this problem for the next precise/stryde nail. They need an iron-containing metal for the magnetic mechanism no? But iron-containing alloys like stainless steel can sometimes have corrosion when it rubs against itself no? So what then are they screwed or are there other engineering / materials science ways around this problem?

Its the crevices in the device that facilitate the corrosion. Any crevice or gap will create a oxygen concentration and pH gradient and many other factors that exacerbates corrosion.

So in other words, its partly a material issue, but also an mechanical issue due the shape of the nail itself.
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SpeedDialer

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Re: Questions for people who understand the metal alloys used in the LL nails
« Reply #3 on: November 16, 2022, 11:28:15 PM »

Dr assayag disputed betz claim in one of the comments saying that it also has a corrosion issue.

So precise 2.2 doesn't have that many problems with corrosion?
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