
New steel treatment could enable lighter, stronger, cheaper cars (2015) - GregBuchholz
http://newatlas.com/flash-bainite-automotive-testing/40774/?li_source=LI&li_medium=default-widget
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Osiris30
"Japan making steel 20-30% lighter and 25% stronger than the toughest high-
tensile steel at the same price":

[http://www.nextbigfuture.com/2016/07/japan-making-
steel-20-3...](http://www.nextbigfuture.com/2016/07/japan-making-
steel-20-30-lighter-and-25.html)

~~~
NamTaf
There's a number of high-strength steels like this. Bisalloy [1] are an
Australian group that produce Bisplate and SSAB [2] are a Swedish company that
make similar products under the Weldox/Strenex/Hardox brands. As you mention,
Nippon Steel also make a range of them.

That said, neither is quite like this flash bainite. Both are very hard
steels, so manufacturing and fabrication techniques need to suit the steels at
hand. For example, machining the steels I listed can be very difficult and
murders tooling bits compared to machining mild steel. Welding can also be
difficult and usually involves significant preheating and post-weld heat
treatment processes. Flash bainite apparently has some benefits in those areas
but to what extent is hard to quantify.

I'd love to know more about this flash bainite process, but their website is
really scant on details. Other sources of info suggest that you weld the
structure together then flash process it afterwards, which I'd assume is
completely useless for anything with complex geometry or substantial size. A
military report [3] of its performance shows that welding after FB treating
literally halves its strength, as you'd expect since the heat of welding is
basically like traditionally heat-treating it over longer durations. In that
sense the ones I mentioned are better because you can more slowly heat treat
them post-welding via more flexible methods that can deal with more complex
shapes. This lets you get restored strength properties because those steels
aren't reliant on a flash-style process.

Where I think this reigns is in its ability to be formed easily whilst still
being strong. Forming those steels I mentioned is a nightmare. In that sense
it would certainly have applications where you can fabricate via fastening
(rivets, bolts, etc.) but it seems to fall short when you need to weld it into
anything more than a small butt-weld of two sheets.

Certainly an interesting development and I'd love to see it realised to a
commercial product as it'd definitely have some uses, but it's not the be-all-
end-all holy grail of steel.

[1]: [http://www.bisalloy.com.au/](http://www.bisalloy.com.au/)

[2]:
[http://www.ssab.com/products/brands/strenx](http://www.ssab.com/products/brands/strenx)

[3]: [http://www.dtic.mil/get-tr-
doc/pdf?AD=ADA588144](http://www.dtic.mil/get-tr-doc/pdf?AD=ADA588144)

~~~
_sammcf
I currently source a number of castings in bainite for ground engaging
agricultural parts and it is what I would call semi-weldable - you wouldn't
rely on a structural mig weld but I've had success with both tig welding and
silver solder for attaching other parts with non-structural joins.

The big win for me is the parts can be air quenched - the slower cooling
eliminates one of the biggest rejection flaws, straightness

~~~
NamTaf
If I'm understanding you correctly, you touch on the point that I (probably
badly) tried to make - by slowly cooling it during heat treatment, you can
post-weld treat it to remedy issues that the HAZ introduces. I'll try to
explain it again because I've probably also confused others.

For example, when I deal with the castings I procure, we mandate that the
supplier either repairs them prior to the heat treatment stage or they must be
fully heat treated again after weld repairs. This helps resolve the otherwise
brittle HAZ. You can do this, because castings are usually quench-and-
tempered, which is a relatively slow process.

Welding stuff like Bis, Weldox, etc. requires both pre- and post- heat
treating in order to let the weld form and also address the HAZ properly
afterwards to restore its strength. You can do this because the processes to
heat treat it are traditional and relatively slow. This lets you get (somewhat
reduced compared to the parent metal) structurally sound levels of strength
out of the weld locality. Because of it, Weldox and Bis both see widespread
use in truck bodies, crane arm trusses, etc.

This is in constrast to flash bainite, which relies on it being a very fast
process. By virtue of it being a fast, tailor-made process you can't just do
it to a complex geometry. By welding it, you dump heat into the weld which
then air-cools slowly as the weld cools, completely running counter to the
flash bainite process that is necessary to produce the strength. That's why
you see a halving in UTS in the mil report I linked in source 3 of my first
post - you simply can't recover from the slower heat-and-cool process without
doing the whole treatment again, and you can only do that on easy geometries
(it seems).

As said, if I understand what you're saying we're essentially saying the same
thing, but I think I phrased it quite badly in my post. Not that you disagree
with me, but it just made me realise that I don't think I worded it well and
wanted to clarify.

~~~
_sammcf
Yep we are in 100% agreement. To rectify my own lack of clarity, the sort of
parts I am talking about are largely prismatic with a handful of holes and
pockets, or for the more complex geometry, not more than around 300x300x300 in
total envelope, so definitely not large.

For reference, bainite has completely replaced 8630 in all ranges of quenching
and tempering as a material for us, and I'm currently in the process of
phasing out most of our Hardox parts in lieu of bainite as well. Haven't used
Bisalloy plate for years due to its even-worse-than-expected machinability.

------
msandford
The bummer here is that you have to heat treat very quickly and that means it
won't work for thicker shapes.

~~~
jdhawk
Serious Question: doesn't induction heating solve some of this? Also, it seems
like they're focusing on tubing type structures.

~~~
msandford
A little, but not really. You can only heat and cool things so fast, and the
time is somehow related to the square of the thickness plus a bunch of
constants.

So if you worked really really hard you might be able to do stuff that's 1/4"
or maybe even 1/2" thick but it'd probably never work for 6" thick.

Yes they're focusing on tube because that's where it can be done. But if you
could get very thick steel that's also stronger than Ti, that'd be AWESOME.
Which is why I'm a little disappointed. This stuff isn't unobtanium, but it is
a bit magical.

------
mabbo
What really interests me is that it sounds like this isn't something high
tech, just "never figured out before". It's a variation on the existing
processes and yields a huge improvement at lower cost.

How many more opportunities are the out there just sitting in front of us,
unconsidered?

~~~
dsfyu404ed
If by unconsidered you mean "yeah we could mix X, Y and Z in different ratios
to make an alloy with different performance characteristics but it's not worth
doing because there's currently no market for an alloy like that" then there's
s lot.

------
88e282102ae2e5b
How can a metal be more ductile and also perform as well in crash tests?

~~~
cjslep
One view can be taken from applying conservation of energy. As a material
deforms, it is absorbing energy and not transferring it to the vehicle nor the
passengers. A brittle material will absorb less energy before shattering,
letting the rest of the energy then be transferred to where you don't want it
to be.

~~~
Gibbon1
Yeah this is correct. Less often talked about but actually very important, the
amount of energy required to break something[1]. Also as ductile structures
deform under load they tend to redistribute the load more evenly.

[1] Hammer a piece of glass vs a piece of rubber.

------
dsfyu404ed
What's the catch? Weldability, piss poor corrosion resistance/reactivity?

"while aluminum is good for hoods, decklids and door skins, Flash offers
higher strength per pound for structural safety components."

So no more "like a m __ __ _f_ __ __g submarine " commercials or will they
start making submarines out of it too?

~~~
PeterWhittaker
_What 's the catch? Weldability...?_

I've just been chatting with a mech-eng materials specialist friend of mine,
and according to him, you hit it, right there; he writes _hot work will cause
the microstructure to revert to classic regular BCC ferrite which isn 't that
impressive. that's the reason why you can't / shouldn't weld the stuff...
...essentially it's a "cast/quench this part and leave it the hell alone"
material_.

------
emilong
Is anyone aware of other, non-automotive applications being discussed? I might
have missed it in the article but it seemed like they only alluded to any.
Construction? Maybe even aerospace?

~~~
dsfyu404ed
Aerospace would be a big one. The few steel parts in aircraft are usually
highly critical like landing gear attachment stuff and similar. Part of the
reason they're steel is because they're spec'd to outlive the rest of the
airframe by a huge margin and doing that with aluminum is
impossible/impractical depending on the part and the safety margin.

~~~
noir_lord
Also failure mode, Aluminium tends to degrade gradually over time, it's
cumulative and then fail where steel holds it's strength over it's life (as
long as it's not exposed to loads over it's limits) which for a high
impact/load environment like landing gear makes sense I guess.

I'm a keen cyclist and some of the new steel frames are incredibly, they
approach the same weight as aluminium frames with higher strength, better
rigidity and they have (looked after) a basically indefinite lifespan.

I think my next bike will probably be steel.

~~~
Grishnakh
That's funny. My bike is steel; I got it in college 20 years ago, so it's not
new at all. At the time, it was pretty advanced I guess: it's a butted
(triple? not sure) chrome-moly steel road bike by Trek. It's a little over 25
pounds I think, so it's really not that much heavier than comparable aluminum
bikes. The frame's still in fantastic shape even though it's been ridden all
over and not taken care of particularly well, been rained on a lot, etc.

Not long after I got it, it seemed that steel frames became totally passé;
everything went to aluminum, titanium, and then carbon fibre. These days, road
bikes all seem to be either aluminum or CF. And now history repeats itself...

Personally, though, I'm looking forward to ditching it and getting a recumbent
trike. I'm getting sick of having a sore neck and shoulders and hands and
having my arms go numb on long rides.

~~~
noir_lord
If the hand numbness is really bad consider switching to a carbon fork if you
haven't already, on my old aluminium bike the numbness was pretty bad since I
switched to a carbon bike it's largely gone.

~~~
Grishnakh
How is having a stiffer front fork going to help? (My front fork is steel; my
bike is not stiff.)

~~~
noir_lord
It's not so much the stiffness that matters but that carbon damps the 'buzz'
from the road, Steel is better than Aluminium but Carbon is better than both
in my experience.

That said if you are having real numbness problems switching up to a 25mm tyre
(most road bikes will take them) and running at 80psi vs 23mm at 110psi will
make the most difference.

It also depends on the surface you ride on, UK roads are not known for been
particularly smooth (particularly rural two lanes) so the differences are more
marked.

~~~
Grishnakh
Thanks for the advice; I do believe I have a 25mm tire in front (I'll have to
check, but it's not super-thin). But a CF front fork sounds like way more
money than I want to spend on fixing up a 20+ year old bike; if I'm going to
spend any money, I might as well get a new bike, which is why I'm seriously
looking at getting a Catrike: I can get away from the uncomfortable road bike
posture altogether that way, get better aerodynamics, avoid crotch pains, etc.

~~~
noir_lord
Recumbents have a lot to recommend them but I don't like the lack of
visibility in traffic, UK drivers aren't that considerate of cyclists
generally so I at least like to be visible, that said they do really really
move compared to a road bike since the aerodynamic shape helps hugely.

~~~
Grishnakh
I'm in the US, and roads here are really bad for riding bikes on, unless
you're in a very small town or something. (Even that isn't a great place; I
live in a small town currently and the street in front of my house has a 25mph
speed limit, but people are constantly speeding on it, and frequently hitting
cats that cross the road near my house.) That's why I simply don't ride on
roads with cars if I can help it; I mostly stick to rail-trails or towpaths. I
can ride 40 miles on a rail-trail and barely see any cars at all, and
frequently not even any humans.

------
kragen
This is a really exciting development in materials science. It's surprising
and somewhat disheartening that it's taken me ten years to hear about it.

[https://patents.google.com/patent/WO2008042982A2/en](https://patents.google.com/patent/WO2008042982A2/en)
seems to be the Flash Bainite patent application; if I'm reading this right,
he's applied for a patent in the US and Canada, but neither has granted the
patent after ten years.

Note that Flash Bainite is a different material than bainite; Flash Bainite
contains bainite crystals, but also contains crystals of other phases,
including (in the case of AISI 4130) 82.5% martensite. Bainite as such has
been known since the 1920s. I'm not completely clear on whether _sammcf is
talking about this kind of flash-processed steel in their comments or about
some other kind of steel in which bainite plays an important role, though it
sounds like they're talking about this stuff.

Putting the Rearden-Steel-like claims he makes in
[https://www.galtsgulchonline.com/posts/c0a47/hi-my-name-
is-g...](https://www.galtsgulchonline.com/posts/c0a47/hi-my-name-is-gary-cola-
developer-of-flash-bainite-technology) in context (thanks NamTaf!), the 2080
MPa strength he's claiming there is within a stone's throw of thin music wire,
which is far and away higher than that of any other steel. But there's a huge
difference in that the 10% elongation at break he's claiming is truly
astounding — more like a plastic than a metal. Normal steels break at about 1%
elongation, aluminum typically around 3%. Nylon 6,6 is typically around 30%.

The ASM HTPro article
[http://www.asminternational.org/documents/10192/17082024/Pag...](http://www.asminternational.org/documents/10192/17082024/Pages+from+HTPro_December_2013_amp17111.pdf/61afa899-7863-4f83-9d5e-a7caa5e22eba)
says they got UTS of 1.99 GPa and 10.2% total elongation for "flash processed
AISI 4140". I'm not sure yet how much of that elongation is plastic, though
judging by the OP's photo of the crumpled thing, maybe most of it.

Bringing those two facts together, it would seem that it's substantially less
stiff than ordinary steels, which means that even if all the claims are true,
it won't replace them in uses where stiffness matters more than strength —
uses like compressive structural members. Furthermore, the strengths discussed
so far are ultimate stresses (after plastic deformation is exhausted), not
yield stresses (stresses from which the steel will spring back), which may be
unspectacular.

In short, it's not a better steel. If these claims are true, it is in effect
an entirely new class of material, that just happens to be _made_ out of
steel.

Since you reach the Flash Bainite state by quenching, it seems likely that
it's metastable and will eventually decay back into a more ordinary steel, but
that's true of austenite too — for human applications, metastability is as
good as stability if the time to relaxation is measured in billions of years.

------
tomhoward
This looks like a hoax to me.

I can't find any coverage of it in any authoritative news sources.

If you google the address given on the company's website, it points to
"Sculptors Fitness Center".

Does any one have any knowledge to suggest that it's anything other than a
hoax?

~~~
honkhonkpants
Here's a detailed metallurgical survey of this material.

[http://www.dtic.mil/get-tr-doc/pdf?AD=ADA588144](http://www.dtic.mil/get-tr-
doc/pdf?AD=ADA588144)

------
lucio
Very nice, sounds like Rearden Steel, if you excuse my objectvism

~~~
cornchips
Objectivism Shrugged :-)

~~~
NamTaf
This is an amusing statement given it seems like he's a bit of a Randian:
[https://www.galtsgulchonline.com/posts/c0a47/hi-my-name-
is-g...](https://www.galtsgulchonline.com/posts/c0a47/hi-my-name-is-gary-cola-
developer-of-flash-bainite-technology)

