Published on May 20th, 2009 | By: firstname.lastname@example.org
Ceramics in TransportationPublished on May 20th, 2009 | By: email@example.com
[Image above] Credit: Tagosaku; Flickr CC BY-ND 2.0
Engine designers are always looking for alternative approaches to lower cost and emissions and increase fuel economy and performance. One approach to improve automobile designs is through material substitutions. Ceramics may be the enabling technology for many critical components in engines of the future because of their unique heat, wear, and corrosion resistance, light weight, and electrical and heat insulation.
Ceramics have been important in automobiles from the beginning, in spark plug insulators and glass windows (early 1920s). Virtually all catalytic converters in modern automobiles have ceramic honeycomb supports for the catalyst, which has been instrumental in reducing automobile exhaust emissions. Most modern cars also use ceramic oxygen sensors in concert with computer controls to optimize combustion and reduce exhaust emissions.
Computer controls and other electronics in automobiles use a large number of ceramic substrates and components which are critical to the performance of the devices. Also, numerous electrical motors are used in modern cars for automated adjustment of seats, windows, etc. Ceramic magnets are used in many of these motors. Recently, ceramic components have been introduced in fuel systems and valve trains of heavy-duty diesel engines.
Cars of the future may have ceramics in internal engine structural parts; in wear-resistant applications in fuel systems; and in additional components in valve trains, such as valves and valve seats. Futuristic cars also may use ceramic fuel cells for near-emission-free operation.
Better braking with composites
Ceramic composite brake rotors, standard equipment on Formula One racecars, are now being offered on select high-performance passenger vehicles, including any Ferrari, most Lamborghinis and Porsches, the Bentley Conti GT Diamond and the Audi RS4. These ceramic brakes reduce vehicle weight by more than 10 pounds, resist heat-induced fading and are expected to last the life of the vehicle. Pad life has tripled and handling is improved because of reduced unsprung weight (the mass of the body and components not supported by the suspension).
A similar type of ceramic composite brake manufactured by Starfire Systems is being tested by the motorcycle racing market, including Honda, Yamaha, Kawasaki, Suzuki and Harley Davidson. Motorcycle racer Jason DiSalvo rated Starfire System’s new brakes “a 12 on a scale of one to 10.” His rating followed a three-day evaluation of a 2004 Yamaha YZF-R1 motorbike equipped with the company’s composite brake rotors. These rotors are manufactured using Starfire’s proprietary polymers and high quality carbon weaves.
Unlike conventional steel discs, these types of rotors actually perform better as their temperature increases. They have proven capable of increasing fuel efficiency, acceleration, braking consistency, and total life-span. These benefits are realized while improving braking and handling performance even at-the-limit. With less un-sprung mass, such rotors offer the potential for components at all corners of a vehicle to be engineered for reduced weight.
Ceramic clutches a big hit with Jay Leno
Car buff and famous talk show host Jay Leno recently raved about the ceramic composite clutch used in Porsche’s Carrera GT. After a test drive he said: “…we did around 50 burnouts, trying to find the best way to minimize wheelspin off the line. It never slipped and kept working fine. The Carrera GT will sprint to 60 mph in just 3.6 seconds, turn 131.6 mph in the quarter and top out at 205 mph…thanks to the ceramic clutch, you can do those 0-to-60 runs over and over again.” The engine run-out speed is over 20,000 rpm, according to Porsche.
The Carrera GT’s multiplate clutch is lighter (7.7 lb or 3.5 kg) and smaller than any comparable unit, leading to a weight reduction of more than 50% compared to a conventional clutch used in a Porsche