Abstract: A ferrographic apparatus and method incorporate a priming operation that moves a priming fluid, in a direction opposite to the flow direction subsequently followed by the sample fluid, through a fluid pathway including the flow chamber. The fluid pathway is configured to facilitate dissipation of any gas bubble introduced into it during the priming operation and to reduce adventitious deposition of specimen material at locations other than the substrate. Sample fluid to be analyzed is added to the reservoir so as to form a bubble-free interface with the priming fluid, and the direction of movement through the flow chamber is reversed. The resulting continuous fluid column is advanced through the fluid pathway so that the sample fluid enters the flow chamber through the inlet port and passes through the magnetic field gradient, exiting through an orifice at the opposite end of the flow chamber serving as the outlet port.

Abstract: A flow unit especially useful for closed-channel Ferrographic analysis comprises a glass substrate, a plastic platen, and an elastomeric gasket sheet disposed between them. Holes in the gasket sheet form flow chambers. Opposite free ends of the gasket sheet extend beyond the edges of the substrate and of the platen so as to allow pulling the ends in opposite directions parallel to the surface of the substrate and thereby shearing the bond between the substrate and the gasket.

Abstract: A flexible fluid dispenser includes a flexible fluid-containing vessel which has a seal which seals a top wall of the vessel to a bottom wall and is shaped to concentrate in a region thereof forces resulting from pressure generated by applying a force to the dispenser. The dispenser further includes a shield shaped to direct fluid released from the dispenser in a desired direction. When a sufficiently large force is applied to the dispenser, the weaker top or bottom wall of the vessel ruptures, or opens, at the concentration region of the seal. The released fluid is then directed by the shield in the desired direction.

Abstract: A flexible fluid dispenser includes a flexible fluid-containing vessel which has a seal which seals a top wall of the vessel to a bottom wall and is shaped to concentrate in a region thereof forces resulting from pressure generated by applying a force to the dispenser. When the resulting force is sufficiently large, the weaker top or bottom wall of the vessel breaks, or opens, at the concentration region of the seal. The opening has dimensions which approximate the dimensions of the force-concentrating region of the seal.

Abstract: A technique for evaluation of various firearm and projectile wear parameters. A debris collector constructed in accordance with the invention includes a receptacle coated with a collecting medium capable of trapping the particles exhausted from a firearm. The receptacle is formed of a fairly ductile material, such as metal foil, so that it is easily penetrated when a projectile is fired into the apparatus. The preferred collecting medium is a polymer blend of white petrolatum and paraffin wax, which exhibits ideal receptivity to impinging particles, while retaining excellent solubility, temperature stability, and shelf life. An appropriate container serves to support and enclose the collecting medium.The collecting medium is then removed from the receptacle for further analysis. It is liquefied by dissolving it in a suitable carrier fluid such as by applying heat or a solvent. The result is a clear liquid containing suspended wear particles. The clear liquid can be visually inspected.