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The preferred method of switching the very high currents and voltages present in electromagnetic launch systems is to use arrays of solid-state devices. The effort to reduce the overall switch mass and volume has generated interest in advanced high-power, high-temperature semiconductor materials such as silicon carbide (SiC). Devices produced from SiC are expected to provide significant performance improvements in very high-power switching devices over current devices based on silicon (Si) materials. The performance improvement expectations are based on SiC's superior material properties, most notably for power devices are a bandgap of 3.26 eV (three times that of Si), a breakdown field of 2-4 MV · cm-1 (order of magnitude better than Si), a thermal conductivity of 4.5 W · cm-1 K-1 (three times that of Si), and a saturated drift velocity of 2 × 107 cm · s-1 (two times that of Si). This paper describes the results of recent experiments at the Institute for Advanced Technology at The University of Texas at Austin in which SiC p-i-n diodes arranged in parallel pairs are subjected to high current density pulses. The failure modes of paralleled devices are compared to the failure modes seen in individual devices subjected to high current density pulses (maximum of 234 × 104 A · cm-2). The results show current equalization between paralleled high-voltage diodes when subjected to high current densities, which suggests that high-voltage SiC active devices will also function well in parallel arrangements. [ABSTRACT FROM AUTHOR]

Discusses the problems experienced in estimating the actual current distribution among various silicon controlled rectifier switches in a converter at the University of Texas at Austin Center for Electromechanics. Importance of multiple switching devices in power converters; Results of the electromagnetic finite-element analysis of one leg of the converter; Role of differential reactance in determining the magnitude of the overload.

Describes a lightweight containment system for high-speed composite rotors developed at the University of Texas Center for Electromechanics in Austin. Uses of metallic flywheels; Failure modes and containment of flywheels; Purpose of the rotatable composite containment design.

Presents an overview of the evolution of compulsators (CPA) developed at the University of Texas at Austin Center for Electromechanics. Features of the CPA technology; Function of the CPA; Factors to be considered when designing a CPA.

Describes the sensors developed at the University of Texas at Austin Center for Electromechanics to monitor speed, sense rotor position and detect fault condition. Features of the sensors; Performance requirements for the sensor; Information on current viewing resistor.

Describes the design algorithm used to optimize the railgun bore and integrated launch package at the University of Texas at Austin Center for Electromechanics (UT-CEM) in Arlington. Features of the UT-CEM design code; Development of an electric gun system design code; Fundamental categories used in the gun system.

Deals with a study on three generations of iron-core and air-core compensated pulsed alternators (CPA) conducted at the Center for Electromechanics at the University of Texas in Austin. Assumptions used in the point designs and comparisons; CPA design and performance; Switch design and performance.

Presents an overview of the Cannon-Caliber Electromagnetic Gun (CCEMG) launcher design and describes the testing performed at University of Texas at Austin, Center for Electromechanics (UT-CEM) and U.S. Army Research Laboratory (ARL). Analysis on cannon-caliber design considerations; Discussion of testing the CCEMG by UT-CEM and ARL; Analysis on launcher performance and inspection; Conclusions.

The Naval Research Laboratory has initiated a program to study the effects of high power launch on railgun barrel materials. A rail used for 20 shots on the medium caliber launcher at the University of Texas at Austin Institute for Advanced Technology was analyzed using a variety of surface and bulk diagnostics. Initial results are presented. [ABSTRACT FROM AUTHOR]

The article focuses on the 2004 Peter Mark Medal for Outstanding Contribution to Electromagnetic Launch Technology winner Mr. Francis Stefani of the Institute for Advanced Technology at the University of Texas at Austin, Texas. Stefani's interest in electromagnetic launch began soon after he received a Bachelor of Science degree in mechanical engineering from the University of Illinois in 1981, when he joined what was then the Westinghouse Marine Division and is now Northrop Grumman. There, he participated in writing the proposal for the first electromagnetic tank gun study.