Vanderbilt University

B6 Sigma, Inc.

The United States of America As Represented by the Department of Energy

Daniel A Hartman

Mark J Cola

George E Cook

Alvin M Strauss

Don Mitchell Wilkes

Paul Fleming

David R Delapp

David H Lammlein

Vivek R Dave

Robert E Swanson

Geremy Kleiser

Robert W Carpenter, Ii

C Robert Kline, Jr

Joel W House

Vivek R Dave'

The present inventions provide methods of manufacturing methods for case metallic materials for munitions that have high enthalpic energy release and controlled fragmentation and breakup enabling fragment speeds up to twice what is otherwise possible in explosively driven metal systems, and munitions made by such methods. Embodiments of the invention involve the thixotropic processing of energetic materials such as aluminum together with high density materials such as tantalum or tungsten to achieve material microstructures with a bulk density equivalent to steel, but with the energy release potential of materials such as finely dispersed aluminum powders. Such methods of mixing and blending of high energy and high density materials can provide a microstructure that has large density and shock impedance differences over length scales of 10-100 microns, resulting in enhanced materials fragmentation in the shock or brisant loading regime, incipient melting at the lower melting point constituents, and additional enhancement of fragmentation in the gas-dynamic expansion phase of munitions breakup. Additionally, the present inventions provide a range of surface and near-surface processing methods to enhance spall and ejecta from conventional munitions systems, enhancing munition breakup and reactivity as well.

Structurally sound reactive materials

A projectile formed from dissimilar materials. The projectile includes a metallurgical interlayer that joins the dissimilar materials together. The metallurgical interlayer also matches the shock impedance of the two materials to prevent delamination during launch and during impact.

Composite projectile

An apparatus and computer program are disclosed for processing at least one workpiece using a rotary tool with rotating member for contacting and processing the workpiece. The methods include oscillating the rotary tool laterally with respect to a selected propagation path for the rotating member with respect to the workpiece to define an oscillation path for the rotating member. The methods further include obtaining force signals or parameters related to the force experienced by the rotary tool at least while the rotating member is disposed at the extremes of the oscillation. The force signals or parameters associated with the extremes can then be analyzed to determine a lateral position of the selected path with respect to a target path and a lateral offset value can be determined based on the lateral position. The lateral distance between the selected path and the target path can be decreased based on the lateral offset value.

Lateral position detection and control for friction stir systems

Friction stir methods are disclosed for processing at least one workpiece using a rotary tool with rotating member for contacting and processing the workpiece. The methods include oscillating the rotary tool laterally with respect to a selected propagation path for the rotating member with respect to the workpiece to define an oscillation path for the rotating member. The methods further include obtaining force signals or parameters related to the force experienced by the rotary tool at least while the rotating member is disposed at the extremes of the oscillation. The force signals or parameters associated with the extremes can then be analyzed to determine a lateral position of the selected path with respect to a target path and a lateral offset value can be determined based on the lateral position. The lateral distance between the selected path and the target path can be decreased based on the lateral offset value.

A friction stir system for processing at least a first workpiece includes a spindle actuator coupled to a rotary tool comprising a rotating member for contacting and processing the first workpiece. A detection system is provided for obtaining information related to a lateral alignment of the rotating member. The detection system comprises at least one sensor for measuring a force experienced by the rotary tool or a parameter related to the force experienced by the rotary tool during processing, wherein the sensor provides sensor signals. A signal processing system is coupled to receive and analyze the sensor signals and determine a lateral alignment of the rotating member relative to a selected lateral position, a selected path, or a direction to decrease a lateral distance relative to the selected lateral position or selected path. In one embodiment, the friction stir system can be embodied as a closed loop tracking system, such as a robot-based tracked friction stir welding (FSW) or friction stir processing (FSP) system.

A method for determining the quality of an examined weld joint comprising the steps of providing acoustical data from the examined weld joint, and performing a neural network operation on the acoustical data determine the quality of the examined weld joint produced by a friction weld process. The neural network may be trained by the steps of providing acoustical data and observable data from at least one test weld joint, and training the neural network based on the acoustical data and observable data to form a trained neural network so that the trained neural network is capable of determining the quality of a examined weld joint based on acoustical data from the examined weld joint. In addition, an apparatus having a housing, acoustical sensors mounted therein, and means for mounting the housing on a friction weld device so that the acoustical sensors do not contact the weld joint. The apparatus may sample the acoustical data necessary for the neural network to determine the quality of a weld joint.

Growing community of inventors

Fairhope, AL, United States of America

Daniel A Hartman