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scandium

Qman

Qman

Monkey
Feb 7, 2005
633
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LordOpie

LordOpie

MOTHER HEN
Oct 17, 2002
21,022
3
Denver
scandium bikes are a great search feature on ebay since most people don't know it can make awesome bikes.
 
disasterarea

disasterarea

Monkey
Jan 26, 2003
137
0
Westy said:
Golf sucks.
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And here was me thinking a flat tyre in deep mud does that quite well too. You live and learn eh. Really though, I find being out having a game of golf with my wife and my parents is one of the better things. I confess, I do suck at it, but that's not the point of playing.

Back to topic, if scandium is such a wonderful material, how come the only bikes I "see" of the stuff are usually XC jobs and not the heavier duty ones e.g. dj, am, dh etc...? Cost? Pain in the butt to work with? But they said that about Ti too didn't they?
 
Reactor

Reactor

Turbo Monkey
Apr 5, 2005
3,976
1
Chandler, AZ, USA
disasterarea said:
And here was me thinking a flat tyre in deep mud does that quite well too. You live and learn eh. Really though, I find being out having a game of golf with my wife and my parents is one of the better things. I confess, I do suck at it, but that's not the point of playing.

Back to topic, if scandium is such a wonderful material, how come the only bikes I "see" of the stuff are usually XC jobs and not the heavier duty ones e.g. dj, am, dh etc...? Cost? Pain in the butt to work with? But they said that about Ti too didn't they?
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Probably because scandium and Titanium are both expensive the cost of producing a three pound frame is a lot less than using it to build a 12 pound DH frame.
 
johnbryanpeters

johnbryanpeters

Hero
Sep 27, 2001
36,678
18,023
Making moss sad in New Haven, Vermont
Doesn't sound as though it's liable to get cheap...

http://doc.tms.org/ezMerchant/prodtms.nsf/ProductLookupItemID/JOM-0302-35/$FILE/JOM-0302-35F.pdf?OpenElement

"Scandium, a novel alloying element for aluminum, is mined and processed in Zhovti Vody, Ukraine, the only primary scandium mine in operation in the world."

Scandium-reinforced aluminum alloys represent a new generation of high-performance alloys that display numerous advantages over high-strength aluminum alloys. Scandium-reinforced alloys are much stronger than other high-strength alloys, exhibit significant grain refinement, strengthen welds, and eliminate hot cracking in welds. These alloys also exhibit a good resistance to corrosion as shown by recent studies. A review of their mechanical, microstructural, and corrosion characteristics shows that scandium-reinforced alloys can be usefully employed in aerospace, sports, transportation, and process industries. The information on scandium reinforced alloys is scanty; very little has been published on the mechanical, microstructural, and corrosion behavior of these alloys.
 
buildyourown

buildyourown

Turbo Monkey
Feb 9, 2004
4,832
0
South Seattle
The actual material cost is very little of the price of the frame.
12# of Ti isn't really that expensive if you buy it in a chunk. It's manipulating it into tubes that gets expensive. A Ti double butted tube costs $200-300 each.

I would guess that we haven't seen Scandium in dh bikes yet because the tubes don't exist. There isn't enough of a market to make it worth while so Easton doesn't see the point in it. It wouldn't really save than much weight off of a DH bike anyways.
A major design consideration for aggresive use bikes is wall thickness and dent resistance. As the strength of your material goes up, your wall thickness goes down, which sucks if you're chucking rocks at your downtube.
 
Qman

Qman

Monkey
Feb 7, 2005
633
0
buildyourown said:
The actual material cost is very little of the price of the frame.
12# of Ti isn't really that expensive if you buy it in a chunk. It's manipulating it into tubes that gets expensive. A Ti double butted tube costs $200-300 each.

I would guess that we haven't seen Scandium in dh bikes yet because the tubes don't exist. There isn't enough of a market to make it worth while so Easton doesn't see the point in it. It wouldn't really save than much weight off of a DH bike anyways.
A major design consideration for aggresive use bikes is wall thickness and dent resistance. As the strength of your material goes up, your wall thickness goes down, which sucks if you're chucking rocks at your downtube.
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listen to the machinist. he knows his $hit.
the wall thickness of my scandium bike is ~.030"
I've abused the hell out of it but have somehow managed to keep it dentless so it's still solid. still, tapping on it with a fingernail makes it sound like it's made of plastic.

put me on the 'golf sucks' list.
 
Changleen

Changleen

Paranoid Member
Jan 9, 2004
14,532
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So to be clear Scandium is used as an alloying agent for Aluminium and at a tiny percent like I think 0.2% Scandium — it’s not actually ‘Scandium Alloy’, it is Aluminium alloyed with Scandium, and very probably also the same other alloying agents we see to make alu better for bikes as well, it’ll be mostly Al, with probably some Cu or Zn or whatever you’re shooting for.
 
HardtailHack

HardtailHack

used an iron once
Jan 20, 2009
7,517
6,855
Changleen said:
So to be clear Scandium is used as an alloying agent for Aluminium and at a tiny percent like I think 0.2% Scandium — it’s not actually ‘Scandium Alloy’, it is Aluminium alloyed with Scandium, and very probably also the same other alloying agents we see to make alu better for bikes as well, it’ll be mostly Al, with probably some Cu or Zn or whatever you’re shooting for.
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It's not cheap stuff- The USGS reports that, from 2015 to 2019 in the US, the price of small quantities of scandium ingot has been $107 to $134 per gram, and that of scandium oxide $4 to $5 per gram.

The cranks I have seem to be decently stiff and are quite light, I think if I was doing decent jumps I'd swap them out as an aluminum/scandium whatever 25mm spindle still scares me, I have cracked and/or bent a few sets of cranks over the years.
 
Changleen

Changleen

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Jan 9, 2004
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In everyday practicalities (e.g, you not the sort of person who just sheared an Alu frame in the middle of a tube because you are a beast) Scandium basically makes welds better. Alu normally fails due to a poor weld or heat treatment side effect if it is inherently strong enough for the given job, it is prone to work hardening and areas with more defects to start with are amplifiers.
 
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HardtailHack

HardtailHack

used an iron once
Jan 20, 2009
7,517
6,855
Was trying to find some broken Kona Scandium frames, I seem to remember a few of them were breaking but I think their normal alloy frames were breaking pretty regularly for a couple of years, before these ones anyway.
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Changleen

Changleen

Paranoid Member
Jan 9, 2004
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HardtailHack said:
Was trying to find some broken Kona Scandium frames, I seem to remember a few of them were breaking but I think their normal alloy frames were breaking pretty regularly for a couple of years, before these ones anyway.
View attachment 157990View attachment 157991
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You see, they did not fail at the welds. Scandium did its job. :thumb:

Both of those look like pretty brittle failures to me, given the location I would guess that is the point where the butting has a stepdown acting a stress raiser, and these dudes are doing mazzive hukz.

Alternatively, being more mean to Kona, I would say because they had teh Scandiumz, their engineers made the frame a bit too thin, and/or the heat treatment practice could be a bit aggressive and where the tube gets thinner it cooled a bit fast and is a bit more brittle than it should be.

I like Kona though, so [prejudice alert] I recon these were some hefty hunks with little to no nuance doing mad hukz because 2010, yo.
 
HardtailHack

HardtailHack

used an iron once
Jan 20, 2009
7,517
6,855
Changleen said:
You see, they did not fail at the welds. Scandium did its job. :thumb:

Both of those look like pretty brittle failures to me, given the location I would guess that is the point where the butting has a stepdown acting a stress raiser, and these dudes are doing mazzive hukz.

Alternatively, being more mean to Kona, I would say because they had teh Scandiumz, their engineers made the frame a bit too thin, and/or the heat treatment practice could be a bit aggressive and where the tube gets thinner it cooled a bit fast and is a bit more brittle than it should be.

I like Kona though, so [prejudice alert] I recon these were some hefty hunks with little to no nuance doing mad hukz because 2010, yo.
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Nah these ones aren't Scandium frames, I couldn't find any pics of badly broken scandium ones but I'm sure I remember reading about them.
I remember Merida not having a great time with Magnesium frames, think they only ran them for a season or two.
 
kidwoo

kidwoo

Artisanal Tweet Curator
Aug 25, 2003
42,146
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Squirtin ketchup n' mustard on charred flesh
HardtailHack said:
Was trying to find some broken Kona Scandium frames, I seem to remember a few of them were breaking but I think their normal alloy frames were breaking pretty regularly for a couple of years, before these ones anyway.
View attachment 157990View attachment 157991
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I got to see one of those in person. The sound of that snap echoed through the trees for like a good 10 seconds :rofl:
 
HardtailHack

HardtailHack

used an iron once
Jan 20, 2009
7,517
6,855
kidwoo said:
I got to see one of those in person. The sound of that snap echoed through the trees for like a good 10 seconds :rofl:
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Ha, not sure I have ever heard a catastrophic frame failure, hearing an old Intense or Orange let go would be pretty pretty awesome...........as long as the rider doesn't get hurt.
 
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