CRITERIA FOR EVALUATING THE CRACK-RESISTANCE OF SHEET MATERIALS

摘要

For products designed and operating on the principle of "damage protection" - which allows for the possibility of the appearance and spread of individual cracks, without leading to general breakdown - evaluations and selection are made with respect to the quality of materials and semimanufactures, based on a complex of characteristics: static strength and crack resistance under static (K_(1s) and K_s) and cyclic (rate of crack growth fatigue - RCGF) loads [1-6]. At the same time, corrosion resistance is maintained at an adequate level. The practical use of crack-resistance criteria has contributed to the design and introduction of new structural materials, possessing better operating properties; these include lamination, based on aluminum alloys with interlayers made from other materials [7]. Most power elements in structures made from aluminum alloys have a developed surface and relatively fine cross sections. As a rule, such elements will fail under conditions of a planar stress state.