Materials Processing Laboratory

Melting and Solidification Laboratory
A special furnace has been constructed to independently control and measure both gradient and velocity. The velocity is controlled by placing the specimen on a weighted platform which can be raised and lowered by a hydraulic pump. A special valving system is then actuated which displaces the specimen through the imposed temperature gradient at a specified rate. The temperature gradient is maintained through a series of heating and cooling stage. Temperature measurement is performed with a series of thermocouples mounted in thermal wells inside the specimen. Data acquisition is fully automated with a 16 channel real-time data display and high frequency logging capabilities. The furnace incorporates the same principles as the traditional Bridgeman furnace, but includes more flexibility in terms of sample size, geometry, and temperature measurement. This furnace permits correlations to be made between alloy composition, cooling rate, and microstructure
{Contact: Dr. Tom Sanders, MSE, Tel: 894-5793}

Impedance Spectroscopy and Electrochemical Analysis and Testing Facilities
Two computerized impedance analysis systems are available for impedance spectroscopy in the frequency range from 1 MHz to 20 MHz: (a) An Electrochemical Interface (Solartron 1286) and a Frequency Response Analyzer (Solartron 1255) interfaced with an IBM/PC/486 computer through software Z-plot and (b) a Potentiostat/Galvanostat (EG&G PAR 273A) and lock-in amplifier (5208 EC) interfaced with an IBM/PC/486 computer through Model 378 software. for measurements of ionic and electronic conductivities and interfacial properties. The two systems are also capable of performing various electrochemical or electroanalytic characterization. A Glove box (Vacuum Atmospheres (TS-4000) is used to handle air-sensitive materials like lithium batteries.
{Contact: Dr. Meilin Liu, Tel: 894-2380}

Corrosion Testing
Two electrochemical corrosion testing systems, including EG&G Models 272 and 273 are available for polarization, potential, and galvanic measurements. An Atomic Absorption Spectrophotometer (AAS) with carbon furnace atomization and mercury cold-vapor accessory (Varian SpectrAA-300 with DTA-96, VGA-76, and MCA-90) are available for solution analysis for metallic ions.