A shaped part and a method for forming the shaped part from a lightweight metal or alloy by extrusion of a slug performed along a pressing axis. The shaped part is formed in at least one region with a deviation from a basic form that is rotationally symmetrical with respect to the pressing axis. The symmetry-deviating region extends over a wall portion of the shaped part that is formed by backward cup extrusion with a normal vector extending predominantly orthogonally in relation to the pressing axis. The same extruding operation forms a structure that surrounds the pressing axis, on a sheet-like base of the shaped part that adjoins the wall portion and has a normal vector extending predominantly in the direction of the pressing axis on the side thereof opposite from the wall portion. In a region of lowest wall thickness of the wall portion at the transition to the base, the quotient of this wall thickness in mm and an average curvature (1/r) in mm.sup.−1, formed at the transition, is greater than 0.03 and/or, in an at least predominant region of the base-wall transition when seen in the circumferential direction, the ratio of the wall thickness to the base thickness is less than 1.0.

A shaped part and a method for forming the shaped part from a lightweight metal or alloy by extrusion of a slug performed along a pressing axis. The shaped part is formed in at least one region with a deviation from a basic form that is rotationally symmetrical with respect to the pressing axis. The symmetry-deviating region extends over a wall portion of the shaped part that is formed by backward cup extrusion with a normal vector extending predominantly orthogonally in relation to the pressing axis. The same extruding operation forms a structure that surrounds the pressing axis, on a sheet-like base of the shaped part that adjoins the wall portion and has a normal vector extending predominantly in the direction of the pressing axis on the side thereof opposite from the wall portion. In a region of lowest wall thickness of the wall portion at the transition to the base, the quotient of this wall thickness in mm and an average curvature (1/r) in mm.sup.−1, formed at the transition, is greater than 0.03 and/or, in an at least predominant region of the base-wall transition when seen in the circumferential direction, the ratio of the wall thickness to the base thickness is less than 1.0.

A preparation method of a uniform low stress cone shaped charge liner includes the steps of multi-pass extrusion forming, vibration aging treatment, and cryogenic treatment. The step of multi-pass extrusion forming refers to 4 to 8 passes of extrusion deformation under the actions of a three-dimensional compressive stress and a deformation rate of 5 to 10 mm/s, having a deformation amount of 5 to 50% for each pass. The shaped charge liner prepared by the present invention has high dimensional accuracy, good geometric symmetry, low stress value, and excellent stability in the precise machining process and in use, which may significantly improve the penetration capability and stability of the shaped charge liner of high-explosive anti-tank warheads.

A preparation method of a uniform low stress cone shaped charge liner includes the steps of multi-pass extrusion forming, vibration aging treatment, and cryogenic treatment. The step of multi-pass extrusion forming refers to 4 to 8 passes of extrusion deformation under the actions of a three-dimensional compressive stress and a deformation rate of 5 to 10 mm/s, having a deformation amount of 5 to 50% for each pass. The shaped charge liner prepared by the present invention has high dimensional accuracy, good geometric symmetry, low stress value, and excellent stability in the precise machining process and in use, which may significantly improve the penetration capability and stability of the shaped charge liner of high-explosive anti-tank warheads.

A ring molded article manufacturing method capable of reliably and efficiently producing a ring molded article in which dead metal regions are reduced, and a ring material used for producing the ring molded article, are provided. The present invention relates to the method for manufacturing a ring molded article having two convex portions which respectively protrude on both sides of the ring molded article in a direction of a center axis thereof and extend in a direction of a circumference of the ring molded article. In the manufacturing method, the ring material is placed inside two molds on which concave portions respectively corresponding to the convex portions are formed, in a condition in which the ring material is supported by a region on an outer peripheral side from an outer peripheral side corner in the concave portion of one of the two molds and a region on an inner peripheral side from an inner peripheral side corner in the concave portion of another of the two molds, the ring material is then forged so as to be pressed by the two molds in a direction of a center axis of the ring material, and the ring molded article is thus produced. In addition, the present invention relates to the ring material used for producing the ring molded article.

Various implementations include a ring material used for producing a ring molded article. The ring molded article has two convex portions which respectively protrude on opposite sides of the ring molded article in a direction of a center axis thereof and extend in a direction of a circumference of the ring molded article. A straight line passing through centers of gravity of first and second side regions is inclined by an angle relative to the center axis of the ring material, the first and second side regions are obtained by virtually dividing a one half section of the ring material based on a middle of a maximum height of the ring material in the direction of the center axis of the ring material, and a range of the angle is 7 degrees to 40 degrees.

A method for manufacturing a cold-forged, extruded aluminum alloy tube includes: providing a primary material made of an aluminum alloy material, and a first cold extrusion apparatus; processing the primary material to form a preform; subjecting the preform to a homogeneous annealing by heating to a temperature of about 410° C. to 510° C. and then cooling to a temperature of about 160° C. to 200° C.; testing the hardness of the preform; immersing the preform in a lubricant which is a lipid having a viscosity index equal to or greater than 170, a flash point equal to or greater than 240° C., a pour point equal to or greater than −24° C., and a fire point equal to or greater than 255° C.; and subjecting the preform to cold extrusion.

A fully plated hollow-point bullet and a method of manufacturing the bullet wherein a malleable metal precursor core having a central cavity and a surrounding wall is divided into a series of petals, each petal being separated from one another by an air space, and all interior and exterior surfaces of the precursor core, including individual petals, are thereafter electroplated with a second metal and final formed in a hollow-point pointing die, ultimately producing a more robust bullet and one that expands easier and faster on impact than plated bullets of conventional manufacture.

A fully plated hollow-point bullet and a method of manufacturing the bullet wherein a malleable metal precursor core having a central cavity and a surrounding wall is divided into a series of petals, each petal being separated from one another by an air space, and all interior and exterior surfaces of the precursor core, including individual petals, are thereafter electroplated with a second metal and final formed in a hollow-point pointing die, ultimately producing a more robust bullet and one that expands easier and faster on impact than plated bullets of conventional manufacture.

A fully plated hollow-point bullet and a method of manufacturing the bullet wherein a malleable metal precursor core having a central cavity and a surrounding wall is divided into a series of petals, each petal being separated from one another by an air space, and all interior and exterior surfaces of the precursor core, including individual petals, are thereafter electroplated with a second metal and final formed in a hollow-point pointing die, ultimately producing a more robust bullet and one that expands easier and faster on impact than plated bullets of conventional manufacture.