Thayer School of Engineering At Dartmouth - college shield
home > research > by-discipline >

Materials Engineering Research

Conducting materials research within Thayer School's single unified department of engineering creates a seamless environment where students benefit from a wide range of disciplines under one roof. In addition, Dartmouth fosters numerous opportunities for cross-campus projects such as within the Center for Nanomaterials Research at Dartmouth, which resulted from collaboration between Thayer School and other Arts & Sciences Faculty.

Biomaterials, Soft Materials & Tribology

Orthopaedic biomaterials research at Thayer School takes place within the Dartmouth Biomedical Engineering Center for Orthopaedics (DBEC). Since 1976, DBEC has acquired the largest collection of retrieved joint implant specimens in the world and has systematically identified and solved most problems related to the production, design, and materials of joint replacement technology. Debris generation from polyethylene wear is considered the biggest problem facing joint replacement today. Current research on cross-linked polyethylene is targeting this problem which involves an analysis of the trade-offs between wear resistance achieved by cross links, and toughness and contact fatigue resistance of the polymer. Additional topics include:

  • determination of the rate of oxidation in vivo of polyethylene subjected to new sterilization techniques
  • wear of new metal-on-metal and ceramic-on-ceramic technologies

(Faculty contacts: Kennedy, Collier, Van Citters)

Tribology research focuses on the measurement and prediction of friction, wear, and surface temperatures during sliding in mechanical components. One area of study is the friction and wear of polymers, such as those used in orthopaedic prostheses, with a focus on their wear, contact fatigue and viscoelastic behavior in oscillatory sliding or rolling/sliding contact.
(Faculty contacts: Kennedy, Van Citters)

Wear of nanocrystalline metals and alloys is being studied to understand the wear mechanisms and to model accurately wear rate as a function of grain size. To this end, bulk nanocrystalline Al, Al-Si and Mg will be produced by equal channel angular extrusion of milled powders. We will also produce bimodal grain structures consisting of nanocrystalline and conventionally-grained material, which we expect will have high hardness yet good ductility. The microstructures will be characterized using a TEM and XRD. Such bulk nanocrystalline materials should not suffer from the difficulties of interpreting wear data that occur for coatings and modified surface layers where the grain size and strain often vary throughout the layers.
(Faculty contact: I. Baker, Kennedy)

Electronic & Optoelectronic Materials

Photoelectrochemical conversion of sunlight is an advancing technology for low-cost large area arrays. Work on the use of nanostructured ZnO in combination with semiconductor and metallic nanoparticles is being pursued to create environmentally friendly materials for this application.
(Faculty contact: Gibson)

High power density magnetic components for dc-dc power converters are being developed using microfabrication techniques. The small size and fast response time of these high-frequency converters will make them advantageous for power delivery to low-voltage microprocessors and other digital systems.
(Faculty contact: Sullivan)

Thin Films, Nanocomposites & Nanostructures

See also Microelectromechanical Systems

Low-power alternatives to conventional CMOS technologies are being investigated—in particular, the use of nanomagnetic ring elements as logic gates and memory elements. These systems retain information in the absence of power, potentially allowing computational devices to be powered up and down without rebooting.
(Faculty contact: Gibson)

Directional recrystallization processing of a variety of materials involves both experiments and computer-based simulations. The work aims to relate processing conditions to the initial microstructure in order to predict, and ultimately to control, microstructural evolution.
(Faculty contact: I. Baker)

Nanostructured magnetic materials research involves development of new magnetic alloy compositions via casting, and processing them using a variety of techniques including mechanical alloying, sputtering, and electroplating. Applications of these magnetic materials will range from on-chip transformers to high-temperature turbine power generators. The clinical applications of using magnetic nanoparticles are also under investigation.
(Faculty contacts: I. Baker, Sullivan)

High Temperature Materials

High temperature magnetic materials are characterized by relatively high saturation magnetization, low coercivity, and high permeability (magnetically soft). These materials will be used in electric airplanes, ships, and automobiles. The major task is to improve high temperature mechanical strength.
(Faculty contact: I. Baker)

Intermetallic compounds show great promise as structural materials for high-temperature applications because of their high strength and resistance to oxidation and corrosion. However, many intermetallic compounds are brittle at ambient temperatures. Current research aims to understand the causes of brittle fracture and to observe the yield anomaly in these compounds.
(Faculty contact: I. Baker)

High-strength quaternary alloys with ultrafine microstructures result from a combination of spinodal decomposition and atomic ordering transformations. Research aims to relate the progression of these transformations to bulk properties such as strength, hardness, and ferromagnetism. Such high-strength low-density alloys would have many industrial and aerospace applications. Some of this work is performed in collaboration with Oak Ridge National Laboratory and also the University of Sydney.
(Faculty contact: I. Baker)

Ice Physics & Engineering

Ice plays a significant role in a number of issues such as global climate and oil and gas recovery operations, as well as having a major effect on transportation, infrastructure, and industry. Thayer School's Ice Research Laboratory offers extensive facilities to study this complex and pervasive material. Some projects collaborate with nearby USACE Cold Regions Research and Engineering Laboratory.

Ice mechanics research is conducted to determine physical processes that underlie brittle failure on scales large (Arctic) and small (laboratory). The current goal is to relate failure of the arctic sea ice cover and fracture during ice interaction with off-shore engineered structures to processes such as wing-crack and comb-crack formation and the development of shear faults. The underlying hypothesis is that brittle compressive failure is a scale-independent process driven by intermittent frictional sliding and stable crack growth. The hypothesis is applicable to other brittle materials as well, such as ceramics, rock, and minerals.
(Faculty contact: Schulson)

Microstructural characterization is crucial to understanding the effects of microstructure and impurities in ice. Researchers here pioneered a way to use the scanning electron microscope (SEM) to study the impurities in uncoated ice and have recently developed a way to gather precise orientation information from ice using electron back scatter patterns (EBSP). Dartmouth engineers are also investigating the type and location of impurities in polar ice cores using a confocal Raman microscope. These efforts will further scientists' understanding of the effect of microstructural properties of ice on the mechanical behavior of ice sheets and glaciers and help paleoclimatologists better interpret the ice core record.
(Faculty contact: I. Baker)

Ice adhesion—causing the icing of airplanes, ships, roofs, and power lines, as well as icy roads and bridges—is a costly and dangerous problem. Because ice strongly adheres to just about everything, including hydrophobic material, several prior empirical attempts to develop durable ice-phobic coatings have failed. A solution requires a fundamental understanding of the physical mechanisms of bonding between ice and other solids, the structure and properties of ice/solid interfaces, and the nature of ice adhesion. Thayer School researchers are studying the fundamental interactions that contribute to ice adhesion strength, and are developing active de-icing techniques including the low-power method of pulse electro-thermal de-icing (PETD).
(Faculty contact: Petrenko)

Victor Petrenko's Ice Engineering (summary)