摘要:
The invention comprises a method and apparatus for equal channel angular extrusion (ECAE) of flat billets to control material structure and properties. The improvements of the method include the special systems of billet orientations, billet lubrication, billet ejection from dies, and a press/die control system those eliminate surface cracks, flashes and billet reshaping or deburring between passes. Therefore, multi-pass ECAE becomes a cost-effective industrial operation and may be applied to large billets.
摘要:
Method and apparatus for fabrication of large thin parts, such as panels having integral stiffeners arranged in any desired pattern, for superplastic and semisolid forming of complicated components, and for consolidation and bonding of powder and composite materials into flat products, include forging-rolling between a flat die and a circular die with a ratio of a contact length between the circular die and a billet to a billet thickness between 20-75 that prevents a material flow in a rolling direction and extrudes the material into die cavities. The circular die is formed as a ring-shaped element sliding along cylindrical guide surface. Both dies are displaced by press to squeeze and forge a billet into a product. For semicontinuous processing of very long parts, the dies are divided into a plurality of sectioned elements which are periodically introduced into a working zone.
摘要:
Described is the production of a metal article with fine metallurgical structure and texture by a process that includes forging and rolling and control of the forging and rolling conditions. Also described is a metal article with a minimum of statically crystallized grain size and a uniform (100) cubic texture.
摘要:
A method of plastic deformation of metals, alloys and other crystalline materials for controlling their structure and texture comprises the steps of extruding a workpiece through two intersecting passages having equal cross-sections corresponding to a cross-section of a workpiece, the pressing including determining during each passage of a workpiece three main directions corresponding to a flow direction, a perpendicular to the flow plane, and a perpendicular to the first mentioned and second mentioned directions, changing the directions during placement of a workpiece in its initial position for each passage relative to a corresponding position in a predetermined passage by turning the workpiece by a predetermined angle around axes of the main directions, and cyclically repeating the method.
摘要:
Unique methods and apparatus are provided for deformation processing of advanced materials using this invention. Enhanced physico-mechanical properties are obtained by extrusion through a die assembly with two channels having equal cross sectional areas under near frictionless conditions. Also, large work pieces of advanced material can be intensively deformed by simple shear forces in a selected manner to produce the specific desired material characteristics. The results of applying the process to the working of cast metals, structure refinement and ductilization of brittle materials, structure-and texture-formation of the special alloys, and compacting of powder briquettes produces enhanced material characteristics in the finished product.
摘要:
A shear-extrusion method of severe plastic deformation for fabrication of metal shapes with ultra-fine structures is described. The improvements of the method include unidirectional shear of any required intensity during one step processing and under high hydrostatic pressures, fabrication of long products with different cross-sections, refinement of low ductile alloys, the increase of productivity and cost reduction. The method can be realized as forward extrusion, backward extrusion, semi continuous extrusion and extrusion of hollow shapes in portal dies with a welding chamber.
摘要:
Described is the production of a metal article with fine metallurgical structure and texture by a process that includes forging and rolling and control of the forging and rolling conditions. Also described is a metal article with a minimum of statically crystallized grain size difference in grain size at any location of less than about ±3%, as well as a dispersion in orientation content ratio of textures of less than about ±4% at any location.