Patent DE-102008033027-A1 (DE)
Title: Increasing strength and ductility of precipitation-hardenable metal materials such as light metal alloys based on e.g. aluminum, comprises transferring the material into a state of solid solution, and rapidly cooling/quenching the material
Inventor: HOCKAUF MATTHIAS
IPC: B21J5/00
Filed: 2008-07-14
Abstract: The method for increasing strength and ductility of precipitation-hardenable metal materials such as light metal alloys based on aluminum, magnesium, titanium, nickel or iron, comprises transferring the materials into a state of solid solution by solution annealing, rapidly cooling/quenching the material, where the dissolved alloying elements are kept in a supersaturated solid solution, intensively shear-deforming the materials in the supersaturated solid solution-strengthened state without or without additional precipitation of alloying elements, and precipitation-hardening the material. The method for increasing strength and ductility of precipitation-hardenable metal materials such as light metal alloys based on aluminum, magnesium, titanium, nickel or iron, comprises transferring the materials into a state of solid solution by solution annealing, rapidly cooling/quenching the material, where the dissolved alloying elements are kept in a supersaturated solid solution, intensively shear-deforming the materials in the supersaturated solid solution-strengthened state without or without additional precipitation of alloying elements, and precipitation-hardening the material to a semi-finished or finished product by cold- or thermal aging treatment of the material. The intensive shear-deformation takes place by cross-sectional, homogeneous pressing or pulling in the channel sections at a temperature (T) of = 120[deg] C or at room temperature, where the channel sections are right-angle to each other and have a pressing channel or pulling channel, which is provided in a matrix (1). The material for the shear-deformation is pressed and/or pulled by the channel sections (2, 3) of the matrix in a single or repeated manner. The material is shear-deformed at an angle (phi ) of 90[deg] . A cross-section of the material remains unchanged during the shear-deformation. A first channel section and/or a second channel section, by which the material is shear-deformed under directional change, consist of partial channels. The material is solution-annealed at a temperature nearer to its solidification point and is subsequently quenched before the shear-deformation is carried out. An external angle (psi ) of the channels of the matrix is 0-90[deg] . After the shear-deformation, a hardening and/or aging treatment takes place at room temperature, elevated temperature or a temperature of 170[deg] C for a time period of 15 minutes. Before the solution-annealing treatment, a raw basic material is provided as a homogenized ingot to an extrusion process for the formation of an input cross-section for the following solution-annealing treatment. The shear-deformation takes place according to equal-channel angular pressing process, equal-channel angular extrusion process, dissimilar channel angular pressing process, repetitive corrugation and straightening process, accumulative roll bonding process, equal-channel angular pressing conform process or incremental equal-channel angular pressing process. The temperature during the shear-deformation of the material is lower than during the subsequent precipitation-hardening and/or cold- or thermal aging treatment of the material. The material is pressed and/or pulled using a stamp or by hydraulic pressure through the first channel section, is changed in an edge- or deflection area (7) in its direction of motion, and is pressed and/or pulled by the second channel section. The precipitation-hardening and/or cold- or thermal aging treatment takes place initially at a first temperature level and finally at a second temperature level.