Patent ID: 6422090
Filing Date: 2002-07-23
Classification: B21J,B21K,G01N

Abstract:
A material testing system, which is capable of imparting high strain test specimen, comprising:a deforming device for controllably and successively deforming a work zone of the specimen in a direction transverse to a longitudinal axis of the specimen so as to define a deformation direction and to produce successive deformations in the specimen, by compressing the specimen between a pair of opposing surfaces of the work zone, and impart cumulative strain to the work zone; a grip assembly for securely holding the specimen at both of two longitudinal ends thereof with sufficient rigidity during each of said deformations such that the specimen, as a result of compressive force imparted by the deforming device to the specimen during said each deformation, does-not experience appreciably any flow elongation along the longitudinal axis, and material flow in the work zone of, the specimen, resulting from each said deformation, substantially occurs outward from the work zone and in a direction transverse to the longitudinal axis and away from the deformation direction, thus producing strained work zone material; and a device for rotating the specimen through a predefined angle after each of the deformations has occurred so as to expose a next successive pair of opposing surfaces of the work zone to the deforming device and, by so doing, present the strained work zone material to the deforming device such that the strained work zone material is deformed again during a next successive one of the deformations; whereby strain is increasingly accumulated in the work zone through repeated deformations between successively changing opposing surfaces of the strained work zone material while volume of the strained work zone specimen material remains essentially constant throughout all the deformations, thus imparting said high strain to the specimen.