Will aluminum Ford F-150 be a rolling beer can?
usatoday.com
usatoday.com
I have two areas of expertise on this matter. First, I was on UW-Madison's competition-winning FutureTruck team about 10 years ago. We were, IIRC, the only team of about 15 other universities that replaced our competition car's (a Ford Excursion) entire frame with aluminum. In addition to replacing many other steel parts/assemblies with aluminum equivalents, we managed to bring the newly parallel hybrid SUV under stock weight... despite adding a large battery pack and motor. The thing I learned from this experience was: even though aluminum has about 1/3 the density of steel, your parts end up being about 50–55% of the steel weight because you need to add more aluminum to maintain equivalent strength. Basically, given the same tensile strength properties of a part, an aluminum one will be about half as heavy.
Second, I worked as a payload mechanical engineer for a number of spaceflight systems. Suffice to say, our base material for consideration was aluminum. Sure, we deferred to steel for certain applications (e.g., ball bearings, rat cage bars, fasteners, etc) and to myriad materials in others, aluminum was the standard. It has a tremendous strength/weight ratio, can be alloyed in many different ways to get different characteristics, is non-magnetic, is relatively cheap, and can have a number of interesting surface coatings applied. About the only major systemic problem aluminum has is that it is difficult to weld. Not impossible, as my FutureTruck experience tells me, but difficult. It didn't matter to us, though, since NASA generally frowns upon welded joints anyway. Too much strength variation due to heat stress and potential for FOD if not ground properly.
Anyway, I've been waiting for the auto industry to catch up to a bunch of college students for 10 years now. Nice to see one of the Big Four finally getting it. And cheers to the smaller car companies that have been doing it for years.
Corrosion is more commonly known as rust, but that's technically reserved for steel (or, more accurately, iron) oxidation. Aluminum certainly corrodes, but it corrodes into aluminum oxide, or alumina, which is actually a ceramic that is stronger than aluminum. In fact, good luck using aluminum without a coating of alumina... it naturally occurs on the surface of atmospherically exposed aluminum. As a result, when a chunk of aluminum is broken off of a larger piece, the material almost immediately forms a protective layer of alumina. It's almost like aluminum self-heals in the presence of oxygen.
Galvanic corrosion occurs when dissimilar metals come into contact amidst an electrolyte solution. In the case of vehicles, that's usually seawater/sea-mist or salted winter roads. While saltwater is also responsible for accelerating normal corrosion, it also plays a part in galvanic corrosion. So yes, having aluminum and steel touching is a recipe for galvanic corrosion, but galvanic corrosion is not black-and-white. Each metal has an anodic index; a high or low anodic index doesn't matter all that much. What matters is the difference between the anodic indices of the touching metals. For aluminum and steel, that difference is quite small, so galvanic corrosion isn't a huge issue, but it's not negligible either.
Galling occurs when the sliding friction of two parts, say a screw and its threaded mate, results in plastic deformation, usually in the more ductile of the two pieces. This generally doesn't come into play in the construction of a vehicle because many parts are attached either by welding or by a bolt-nut combo. Choosing the correct materials for the bolts and nuts (basically, just use hardened, but not stainless, steel) gets rid of this concern in most cases. In cases where one must screw a steel fastener into a threaded aluminum piece, a helical insert is usually prescribed. While many manufacturers make these, we typically used Helicoil for spaceflight ops because they're tested and rated for spaceflight (batch traceability, proper composition docs, etc).
There seems to be a lot of FUD around the new F-150, and as a European, it's hard not to see the similarities with U.S reactions to small turbocharged engines, and smaller vehicles in general.
The 2013 Range Rover has a complete aluminum body (skin and structure), with a 700lb weight reduction for US models.[1]
1. http://www.caranddriver.com/news/2013-land-rover-range-rover...
* Various differences among models some have steel roofs, doors etc.
The bicycle business moved to aluminium a generation ago. For at least a decade carbon fibre has been the material of choice for road bikes. Nowadays if you are from the school of 'steel is real' then you are going to have to buy a cheap 'bicycle shaped object', get something custom handmade or go for something deliberately hipster-retro.
Clearly there have been aluminium bodied cars for some time, even a 'truck' if you count the Land Rover. However, there is aluminium and there is aluminium. I suspect that the new Ford truck has a bit more to it than the Land Rover (or even the Audi A2) has.
In the bike business there is 6 series aluminium and 7 series aluminium, to name the most popular alloys. The original aluminium frames were welded together tubes, for a while 'bonding' was experimented with but that proved to be unreliable. The current state of the art is 'hydroformed' aluminium, welded. The 'hydroformed' frames are works of art, with the metal where you need it for strength, the grain structure also aligned for strength. The tubes are anything but plain cylinders and much more useful for design than was possible in the days of steel.
Does anyone have any more technical information on what the processes and alloys are going to be on this new-fangled truck?
You might consider this to be in the second category, but here is a high-end bicycle maker that does exclusively steel frames: http://www.rodcycle.com/
Here is their advocacy for steel frames: http://www.rodbikes.com/articles/steel.html
Not entirely. http://surlybikes.com/
Steel is still cheaper, easier to fix, and more comfortable.
Without the maganese this would be a series 5 aluminum according to the alloy grade comparison I found.[2]
1. http://en.wikipedia.org/wiki/Birmabright#cite_note-Camm.2C_B...
2. http://www.practicalmachinist.com/vb/general/aluminium-alloy...
But to give potential critics some credit, aluminum can be made very thin, like a beer can, in which case it is flimsy. It can also be made thicker, like the aluminum siding of the 60s and 70s, in which case it may still ding easily and lose its appearance.
This is Ford's flagship vehicle. It cannot just sell well, it must put up amazing numbers. Its the iPhone of the car world.
1) the F-150's gas mileage isn't stellar, but it does even out when hauling.
The rollout of the EcoMod twin-turbo six-cylinder in the F-150 gives me some faith that they're not the usual run-of-the-mill idiots.
Otherwise, I'd welcome not only the weight reduction, but the avoidance of rust and body rot.
[1] http://www.caranddriver.com/reviews/2007-audi-s8-long-term-r...
http://www.motormobiles.de/motor/a2i.jpg
The model was too expensive to produce and was cancelled by Audi in 2005. No aluminum Audis after that except some sport models. It's sort of a hidden gem.
To an outsider, making a big pickup truck from aluminum is like creating a paperweight out of some expensive lightweight material. Isn't the whole point of a pickup to most people (not all) being imposing and bulky? They even mention the 5000 pound weight in advertising, I assume they try to impress that it weighs a lot.
Due to aluminum?
> Isn't the whole point of a pickup to most people (not all) being imposing and bulky?
This is a whole discussion in itself. Modern pickups, to my eyes, look more like cartoons of pickups. The manufacturers (in my mind, especially Nissan and Ford) go out-of-their way to add big, chunky fenders and grills and such. It must sell. And small trucks are disappearing: Ford's Ranger is gone in the US market, and Toyota's Tacoma is now as big as the F150 of a decade or two ago.
Then the rear brakes also had to be fixed for the yearly checkup, normal wearing parts. And the internal heater had a connection problem, discovered when it started being cold enough that it was used (it's an aftermarket job anyway, to connect the car to an electricity outlet and warm up the engine block with a resistor and the interior with a resistor+fan).
I've had the car for six months and from rough memory, spent maybe 400 euros for maintenance.
Aluminum damage to the structural (sub)frame is a whole different beast than in the (non-structural) body panels. Aluminum work hardens when bent. When it hardens it become brittle and can crack from stress and vibration. Any damage has to be completely replaced with fresh metal.
Corrosion is still an issue with aluminum though it tends to self-protect itself. If you really want to mess up something aluminum add some mercury..
Disclaimer: Truck !== Good in Snow
[1] http://www.ford.com/trucks/f150/specifications/view-all/
In other words, less weight + smaller tire == same snow bite. Smaller tire? Cheaper tire. Smaller tire? Less rolling resistance. Lighter spare tire.
Lighter truck? Better gas mileage, better stopping, better cornering. If there is a 1000 lbs less to stop on the snow, that will make a huge difference.
Too many people think that their all-season tires can do everything. They can do everything, but they don't have the dry grip that summer tires do in warm weather, and they don't have the aggressive siping, channels and the tread compound for ice and very cold air temperatures of winter tires. All season tires do everything far worse than their specialty counterparts do, and it demonstrates itself the most every winter.
I drive lightweight RWD sports cars all year round, and we get plenty of snow in Boston. Never have had an issue with winter tires, and sometimes I deliberately seek out empty unplowed parking lots just to have extra fun in.
Snow tires are pretty cheap compared to body work too ;)
On the flip side: how will the ever present salt affect the aluminum body?
All metals will corrode in the presence of salts. Though aluminum does not exhibit rusting like steel does, it will develop a chalky film and pitting in the metal surface when exposed to salt for long periods. I believe that this is aluminium oxide.
Some reading: http://www.boatingmag.com/how-to/maintenance/protecting-alum...
If I still lived in a state that used salt, I would follow the precaution of getting a year round carwash pass and going once a week. Plus, a good underbody coating works well.
1) put them over the back wheel, NOT loose in the bed so they slide. Rope or bungee cords are your friend.
If the bed interior is aluminum, they will have to increase the thickness compared to steel, but it will do just fine at distributing the load to the frame.
Aluminum has a softer surface and will scratch easier. I'm guessing the Aluminum F-150 will come with a bed liner from the factory.
Including the Honda Ridgeline? I thought that was an exception. In any case, you're mostly right, and that design is unlikely to change. Folks who actually use trucks in their work often bolt on various different styles of body: contractor bodies with large storage cabinets on the sides, enclosed van-like boxes, dumping beds, etc.
But frames can certainly be made of aluminum. The East company, which makes flat-bed and dumping trailers for semis, makes frames from aluminum. An unloaded, aluminum-framed flat-bed is very noticeable for its pronounced arch.
The scratchable surface of the bed will be paint, just as in the steel models.
I'm not aware of any true pick-up that uses a unibody design, and probably for the reasons you've stated.
For all that work you'd think these days carbon fibre would be just as good, economically-wise.