Stainless Steel
Monday | 01 January, 2007 | 2:55 am

Flexing those corn-fed muscles

By Abbe Miller

January 2007 - The news of new alternative fuels hit consumers in waves. One day it was plugging a car into a 220-watt outlet, the next it was filling tanks full of used grease from fast-food-restaurant fryers. Understandably consumer skepticism ensued. Only the most forward of thinkers were brave enough to invest in new-fangled vehicles, let alone go trolling for old french-fry drippings to power them. So without a widely accepted replacement to the tried and "crude," the lines at gas stations across the nation continued to grow.

Since the release of E85, the excuses have all but dried up and not a moment too soon. One would have to imagine that it's only a matter of time before the wells dry up, too. The American dependency on oil to fuel its millions of gasoline-hungry vehicles has been an exhausted topic of conversation, but one that hadn't yet propelled the masses toward drastic changes to squelch their petrol addiction. That is, until now.

Stainless steel to the rescue
E85 is a blend of 15 percent good-old-fashioned gasoline with 85 percent ethanol mixed right in. Merriam Webster's dictionary defines ethanol as a colorless, volatile, flammable liquid that is the intoxicating agent in liquors and is used as a solvent and in fuel. It's also known as ethyl alcohol or grain alcohol and it can be used as an alternative to gasoline in any concentration up to 100 percent. The corn-based product quickly emerged as the most affordable, earth-friendly solution out there. The underlying problem with the biofuel, however, was its propensity to corrode the carbon steel that is normally found in vehicle engines. E85 is hygroscopic, meaning that it absorbs and retains moisture. Conventional carbon steel fuel pumps, fuel lines, manifolds and injectors wouldn't stand a chance.

As with any new technology, some modifications to the standard model were required for a successful application in the marketplace. Car manufacturers, most notably the Big Three, had to adjust their way of thinking when it came to developing engines. The result was the formation of the flex-fuel vehicle, which could alternate fuels--in this case, either gasoline or E85. To handle the ethanol, a hearty material that could withstand the corrosive properties was sought after and ultimately found in stainless steel.

"GM has specified stainless steel for the fuel rail since the beginning of the decade, prior to the use of flex-fuel, and the company wanted to position itself so that as alternate fuels are developed, the fuel rails on past model-year vehicles could take advantage of the new breakthroughs," says Matt Hamilton, technical specialist of General Motors' Powertrain Fuel Systems. "GM also didn't want to have to revalidate the fuel system every time an alternate fuel source was made available. By specifying a premium-grade material, GM has confidence that the fuel system will not be a road block to the rollout of alternate fuels."

Stainless steel is no stranger to environments where oxidation and corrosion are prevalent. For that matter, its name comes from its ability to resist stains, corrosion and rust, unlike many of its steel alloy siblings. DaimlerChrysler also adopted the resilient metal as its material of choice for the flex-fuel vehicles that it produces, which will make up more than 25 percent of its fleet over the next few years.

"Stainless steel resists corrosion, and over time ethanol can damage other materials," says Steve Mazure, manager of DaimlerChrysler Powertrain Planning. "Cost, durability and availability studies put stainless out in front."

Although flex-fuel engines do need a little tweaking, they certainly don't require an overhaul. Parts that need to be formed out of stainless steel are, of course, only those that have direct interaction with the fuel itself. Fuel lines, injector parts and fuel pumps are the most likely for re-engineering. Hamilton says that GM will manufacture its fuel lines and injectors from the material, and even though the price of stainless steel can run a bit higher than carbon steel, the consumer's price tag won't be affected.

"With stainless steel you no longer need to coat the fuel rail," Hamilton explains. "This offsets a majority of the cost. And coating isn't environmentally friendly. With coating you always run the risk of the coating being judged environmentally unacceptable down the road. Coating is also a difficult process to control. The coating depth needs to be taken into consideration when you validate the part. Also, if the coating gets scratched off the part this needs to be factored into your validation plan. With stainless steel you avoid all of this."

Fill 'er up
DaimlerChrysler and GM will both use yellow gas caps to indicate which of their cars and trucks are E85 capable, while Ford says it will be reverting to a capless system. Currently GM has more than 2 million flex-fuel vehicles cruising down U.S. highways and byways, but some of those drivers might not even realize that their vehicle is equipped for E85. Hamilton says that 2007 models will come with the yellow cap and that current GM flex-fuel-vehicle owners will be supplied with them, as well, to remind drivers that they have the choice to fill up with either gasoline or E85 fuel.

The holding and dispensing of the biofuel at filling stations, as well as its transportation across the states, will possibly result in further applications for stainless steel. Underground holding tanks and pump nozzles would need to be outfitted in stainless steel, as would the tanker trucks that carry the fuel.

Currently there are approximately 1,000 fuel stations across the United States where E85 can be purchased, and that number is expected to double in the next year as more financial incentives become available to service station owners, including government grants up to $30,000 to install the E85 fuel pumps. And as consumers knowingly or even inadvertently purchase flex-fuel vehicles, filling stations won't just want to offer E85, they'll have to.

As of now, Chevrolet, Chrysler, Dodge, Ford, GMC, Mercury, Mercedes Benz, Nissan and Mazda all have flex-fuel vehicles on the market with a grand total of 26 available models. For 2007 GM has increased its E85 offerings to 16 different models and will produce more than 400,000 of the eco-friendly vehicles annually. The company also announced that 20 percent of its cars and trucks will be E85 capable by 2010 and 50 percent by 2012. DaimlerChrysler isn't far behind. With 1.5 million flex-fuel vehicles on the road and plans to up production to 500,000 per year by 2008, the possible choices for consumers are numerous. As for stainless steel producers, a broadened expansion into the automotive and alternative-fuel markets isn't looking too shabby, either. MM

Some say that a reliance on corn could be almost as detrimental as the current reliance on oil, while Midwestern legislators and companies such as Archer Daniels Midland Co. tout ethanol as the fuel of the future.

It is hard to deny that the subsidies divided among those who farm the carbohydrate-packed vegetable seem to outweigh subsidies passed down to farmers of other more nutritional plants. And on top of the special treatment from Capitol Hill, non-supporters say that corn is hogging all of the nation's fertile farmland and that the supposed big fossil-fuel savings aren't worthy of accolades, considering what it takes to process corn into ethanol.

But what are Americans supposed to do? The number of barrels of crude oil that U.S. citizens depend on daily, is unacceptable. Ben Lieberman, senior policy analyst, energy and environment, for the Heritage Foundation, a large D.C. think tank, brought up a discussion that might just make everyone happy.

"Making ethanol out of corn is expensive and there are also questions as to how much more we can make," says Lieberman. "Already, the current mandate is intact in corn prices. So the talk now is, 'Can we make ethanol out of other things?'"

The answer is yes. Researchers are studying which plants will be the most viable substitute for corn, the main ingredient in ethanol. Currently switch grass, a tall prairie grass, is coming out as a frontrunner. The hardy perennial doesn't need to be re-farmed every year, requires little, if any pesticides or fertilizer, and can thrive in the least hospitable patches of soil. But sugar and cellulose-based ethanol comprised of agricultural waste such as corn stalks and husks, are candidates, as well.

What this adds up to, as far as flex-fuel vehicles are concerned, is sustainability. Even if corn is beat out by another plant, alcohol-based fuel has already emerged as a promising alternative to gasoline. It might just have a few kinks to iron out.

"I think that [switch grass as the future of ethanol] is pretty much a Hail Mary," says Lieberman. "But ramping up ethanol use much above today's levels is going to have to require something other than corn. If something else doesn't turn out to be feasible, like switch grass or wood chips, then there are going to be some real limits to ethanol."

Foreign oil will be a part of our past, but how and when remains to be seen. With research and development well underway, it is possible that that future will come sooner rather than later.

By Abbe Miller, from the January 2007 issue of Modern Metals.

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