Issue Date: May 24, 2004
A HAVEN FOR GLASS, CERAMICS
Alfred, N.Y., serves as a nexus of contrasts. The town is celebrating in June the 30th anniversary of the installation of its single traffic light, yet it is home to scientists and engineers who are exploring some of the most advanced materials in the world. Located some 70 miles south of Rochester, it has a population of just 5,000, but it attracts college students from as far away as Turkey, South Korea, and India.
The draw for these students is Alfred University, home to internationally recognized engineering and art programs in glass and ceramics. Founded in 1836, Alfred is primarily a liberal arts institution where more than 160 full-time faculty members serve approximately 2,000 undergraduates and 300 graduate students.
Alfred's School of Engineering includes four materials-based programs: ceramic engineering, glass engineering science, materials science and engineering, and biomedical materials engineering science. The 29 faculty members in these programs include some of the world's best known scientists and engineers in glass and ceramics. The school also includes electrical and mechanical engineering programs. In addition to its undergraduate degrees, Alfred offers a master's degree in the four materials subjects and a Ph.D. in ceramic engineering, materials science and engineering, or glass science.
Many of Alfred's engineering students minor in other fields, and some take dual majors. Chemistry and business are particularly popular minors, though several engineering students minor in the arts. In fact, the engineering school and the art and design school share a building.
The university encourages such exploration, says Rebecca L. DeRosa, assistant professor of polymer science and engineering. "The whole philosophy is that you need to be well-rounded. You don't have to be limited to being just an engineer."
In addition, art and science faculty collaborate with students in both the ceramics and glass programs. In one project, glass science professor Alexis G. Clare aided Jackie Pancari, who at the time was working toward a master's in fine arts degree and is now a visiting assistant professor of art at Alfred. Clare and Pancari bundled glass fibers together to create a sort of fiber-optic paintbrush. Pancari then shined light of different colors into the tops of the different fibers and used the lit brush to create abstract "paintings" on photographic paper.
Matthew M. Hall, an assistant professor of biomaterials and glass science, recently helped Linda Swanson, who is working toward an M.F.A. "She was interested in natural weathering processes--the changes that occur in nature over time," Hall says. "We came up with a few ideas, and she ended up incorporating one of them into a recent show called 'Terrestrials.' " The project was based on "one of the classic science demonstrations that are used for kids. It's like 'Magic Rocks' that you drop into solution and they begin to grow like plants. Linda did phenomenal pieces based on that idea. She essentially created nonliving gardens made out of crystals."
COLLABORATION isn't confined to such projects: Alfred offers a number of courses that bridge the technical and artistic realms. Art, liberal arts, and business majors must take a lab-based science course. Offerings include "Ceramic Science for Potters" and the "Materials in Society" course taught by Steven M. Pilgrim, professor of materials science engineering and undergraduate program director of the School of Engineering.
Students in Pilgrim's course have just completed their "Sears report," in which they select a product from the 1927 Sears catalog, compare it with the modern version of the product, and discuss how changes in materials and the use of materials have affected its performance, price, and breadth of use. The students' labs include making slime and glass, throwing pots, optical demonstrations, and projects with photovoltaic cells.
Even the courses geared for engineering majors provide training in more than just technical skills. In the engineering operations class, students work on a project involving either transparent armor, such as bulletproof glass, or a bone replacement material. Once the students come up with a product, they have to figure out how to make and market it. Then they present it to the faculty--and whoever else shows up--at a "marketing night," competing against each other for the "funds" of the visitors.
Alfred's small size and its emphasis on making the undergraduate life a rich one mean that students can enjoy an experience that they might not get elsewhere. For example, undergraduate classes are taught only by professors, not teaching assistants. "Students work with nationally and internationally renowned faculty from the time they start as freshmen," Pilgrim says.
More than a third of the engineering school's undergraduates are involved in research on campus, typically beginning at the end of sophomore year or in junior year. Another third are involved in off-campus co-op programs, usually for a summer and one semester. The students can keep up with their coursework through the school's distance learning program.
All seniors in the engineering school are required to conduct a full year of research under the guidance of a faculty member, to write a thesis based on the work, and then to present it in a poster session.
Further enriching the undergraduate experience, most of the instrument and equipment facilities are open access, meaning that any student who has learned to operate the equipment can use it. In fact, the undergrads get hands-on training on equipment and instrumentation that even graduate students at other institutions might not get to use, according to DeRosa.
Clare adds that "one of the things that people say about our students is that when they go out into industry they're almost immediately useful because they can run electron microscopes and X-ray equipment and they're very confident in the lab."
Alfred's engineering students head off to a broad range of companies and institutions after graduation. Their destinations include Massachusetts Institute of Technology; Stanford University; the University of Missouri, Rolla; Rutgers University; and Pennsylvania State University. Other students have gone on to the U.S. Naval Research Laboratory in Washington, D.C., as well as Sandia National Laboratories and Oak Ridge National Laboratory. Industry also welcomes Alfred students, who have found their way to companies such as Corning, Pratt & Whitney, CertainTeed, PPG, IBM, General Electric, and Ford Motor.
IN ADDITION TO training students for industry, Alfred collaborates with industry through several on-campus R&D centers, including the Center for Advanced Ceramic Technology. Funded primarily by New York state, this center's mission is to support industry with specialized testing capabilities, consulting, and joint projects, Pilgrim says.
The Center for Glass Research is funded by the National Science Foundation and more than a dozen glass manufacturers. Alastair N. Cormack, newly appointed dean of the engineering school, says the center provides "precompetitive research to companies that would otherwise not be able to invest the resources in that area."
The Whiteware Research Center supports the "dinner-plate-type manufacturers," as Pilgrim puts it, as well as ceramic insulator companies. And the Laboratory for Electronic Ceramics focuses on things like capacitors, fuel cells, other ionic conductors, piezoelectrics, and ferroelectrics.
The research conducted through these collaborative ventures, as well as in solo efforts in Alfred's labs, displays the remarkable depth and diversity of the engineering school's faculty members. Their studies range from implantable scaffolds for growing new bone to sophisticated security tags for retailers.
Hall, for instance, is developing bioactive glasses that can be implanted in the body and gradually converted into bone. These materials can be made by melting oxide and carbonate powders in a furnace. The melt is cooled to form a glass, which is then crushed into a powder. The powder is "packed into the defect site where it rapidly reacts to form a gelatinous plug," Hall says.
Alternatively, producers can utilize the sol-gel process, which Hall describes as the "glass equivalent of making Jell-O." In Jell-O, gelatin added to hot water gradually forms cross-links as the water cools. Similarly, "in the sol-gel process, we use a chemical precursor that links up over time to form a continuous glass network." Hall often uses an organosilane precursor such as tetraethoxysilane.
Unlike the furnace-based technique, which requires temperatures around 1,400 °C, the sol-gel process can be run at room temperature. "That has a few advantages," Hall says. "One is that you can encapsulate organic molecules inside the glass, such as proteins. Another advantage of the sol-gel process is that the resulting glasses are porous, which is useful for bioactive glasses. The porosity allows for the transport of substances such as blood, nutrients, proteins, or growth factors when the glass is implanted into the body."
Hall is currently conducting in vitro tests with these materials. He places the glass in a buffer that mimics the electrolyte concentrations found in human serum, and assesses how well it forms a layer of calcium phosphate--a key component of bone--on the surface of the glass. Efficient generation of such a layer may indicate that the glass could be used in an implant to induce bone formation.
Hall is collaborating with ceramic engineering professor James E. Shelby on a project for Alfred's Center for Environmental & Energy Research. The researchers are studying hollow glass microspheres 100 µm in diameter as a potential hydrogen storage medium. "The idea is that instead of using one huge cylinder of hydrogen that could potentially rupture and result in an explosion, you have these tiny capsules that contain it," Hall says. "So if one should break, only a tiny amount of gas is released."
Hydrogen diffuses out of the microspheres when the glass is heated. "The problem is that the heating process is somewhat slow"--which could be a drawback if the hydrogen were used as an automotive fuel, Hall says. "So Shelby and some of his graduate students came up with a process to heat the glass up more rapidly, thereby allowing the hydrogen to come out very quickly." Shelby's team made the microspheres more responsive to heat by doping the glass with transition metals that absorb infrared radiation.
MICROWAVE RADIATION might also speed up the heating. That technology is also finding application in other researchers' programs, Hall says. Biomaterials professor Subrata Saha is using microwave processing to produce dental ceramics. This technique could reduce curing times for devices such as dental crowns from weeks to a matter of days, Hall says.
Pilgrim, too, is working with ceramics, though he is concentrating on electronic ceramics, principally sensors and actuators that can withstand extreme temperatures. For instance, he is studying ceramics that can function at 10 K and can change shape when placed in intense electric fields. These materials can serve as micropositioners, vibration dampers, or acoustic transmitters and have applications in everything from sonar to medical ultrasound.
Cormack, a ceramic science professor and director of Alfred's graduate school, is interested in computer simulation and atomic-scale modeling of the inorganic oxides that comprise ceramics. He also studies silicate glasses, developing atomic-scale models of their structures and looking at how modifiers such as sodium, calcium, or fluorine migrate through them.
"You can't probe the structure of glass directly like you can crystalline materials," Cormack says. "But once you've got atomic models, you can start predicting property behavior. Then you can figure out how to improve properties by tailoring the composition of the glass."
Cormack also models point-defect behavior, which "governs a lot of the interesting physical properties of materials," he says. "If you're interested in the use of doped zirconia as a solid electrolyte in a solid oxide fuel cell, you're interested in understanding the atomic-scale mechanism by which the oxygen moves through the material. And in order to understand that, you have to know what the point-defect behavior is."
DeRosa is exploring the feasibility of recycling thermoset composites such as the scrap material left over from making car parts--waste that is typically landfilled. The scrap contains polymer; glass fiber, which serves as a reinforcing material; and a filler, typically calcium carbonate.
DeRosa and her team studied whether ground scrap could be incorporated into new composite as filler or reinforcement. In analyzing the performance of the resulting material, the researchers determined that "most of the failure initiates at the interface between the already cured thermoset material and the new resin," DeRosa says. So they are modifying the recyclate--for instance, by reintroducing double bonds into its cured polyester matrix. They are also testing different formulations to find the right amount of filler and fiber to limit such failure.
In another project, DeRosa and a student are working with a new fabrication technique that creates gel-like channels in the surface of glass. Fluid can flow through the channels, making these devices suitable for microfluidic applications.
"Glass corrodes just like metal does," DeRosa explains. "When glass is exposed to water, it interacts with the water and creates a gel-like surface. We can enhance the corrosion process by adding UV light. And because we have UV light in the picture, we can use photolithographic masking to create different channel designs on the surface." The researchers have found that the formulation that is best suited to this technique is a phosphate-based glass.
In a related experiment, the team corroded the entire surface of the glass to form a gel layer. Then they laid down a sol-gel coating, which binds tightly to the silanol groups on the glass surface. The sol-gel coat is porous, making these treated surfaces suitable for microarray slides that can be used to test water for proteins indicative of the presence of contaminants such as E. coli and fecal bacteria.
In Clare's lab, one student is working on producing white light from blue light-emitting diodes (LEDs). LEDs are extremely energy efficient at providing light--unlike incandescent and fluorescent lights, says Clare, who is director of the Industry/University Center for Bioceramics. White LEDs are already on the market, "but they are very harsh, and they have color halos in them. We're trying to create a glass phosphor that will make a good-quality white-colored light from a blue LED and that won't have different-colored halos in it." Clare's student is considering glass compositions containing rare-earth and transition-metal dopants. The dopants will convert the blue light into other colors that can then be combined with the blue light to make white light.
Another of Clare's students is developing glass compositions that grow thin, reflective copper oxide semiconducting films on their surfaces. These materials can be made into optical fibers to channel light in near-field scanning optical microscopes.
A third student is creating thin fibers out of glass that contains an amorphous metal core. These tiny fibers could be used in discreet security tags to limit theft in shops and warehouses.
Just like some of the materials that are its purview, Alfred University's School of Engineering is itself an unusual composite. It is mostly public but partly private. The public part--New York State College of Ceramics--is "a statutory college of the state of New York administered by a private university," according to Pilgrim.
Back in 1862, Congress passed the Morrill Act, which provided states with land that could be sold to finance the formation of "land grant" universities. "But the New York legislature decided that it was not appropriate for the state to be in the education business," Pilgrim explains. "So they took the agricultural and technical components that the Morrill Act would fund and contracted them to a private university--Cornell."
Some 40 years later, Alfred University petitioned the state legislature to start a school of clay and tile working. The university sits on a large clay bank, Pilgrim says, and the industry is an important one in the region. The state still didn't want to be involved in education, so it contracted the College of Ceramics to the private Alfred University.
BY THE 1950S, the legislature's views about education had shifted, and it created the State University of New York. The statutory colleges at Cornell and Alfred became part of the SUNY enterprise.
The College of Ceramics includes both the School of Art & Design and the four materials programs that now reside in the School of Engineering. Those four programs were combined with the privately funded electrical and mechanical engineering programs to create the School of Engineering in July 2003.
Alfred University and the town in which it is located are named for a remarkable ninth-century ruler of southern England. He championed education, the rule of law, and legal and military reforms. According to the university, settlers who arrived in western New York in the early 1800s named their new community in honor of King Alfred because it resembled Winchester, his capital in England.
In its faculty, students, and official guests, the university seeks to emulate the multifaceted King Alfred. It was fitting, therefore, that the person who delivered this year's commencement address at the university was someone who exemplifies the campus' ideal of the well-rounded individual: Chemistry Nobel Laureate Roald Hoffmann.
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