STRUCTURAL AND MECHANICAL PROPERTIES AND FATIGUE IN STAMPED HAMMERS AND PRESSES THE CORRUGATED PLATE SHEET ALLOY ЭИ 878
The results of the study of fatigue properties of the alloy EI 878 (12H17G9AN4) corrugated sheet metal panels made in a hydraulic press to form a block elastic medium in a cold state and sheet-metal hammer in a metal die with heating. The tests were carried out on the cyclic durability on flat specimens cut from the rift zone and the non-deformed sections of panels, the scheme cantilever bending (GOST 25502-76). Corrugated metal panels, stamped on the press elastic medium, showed the best results, although in this case, with both the technologies of production, increased fatigue resistance compared with the initial state of delivery. Discussion of the results is made on the basis of a comprehensive methodology including : the analysis of strain state and alteration of structural and mechanical characteristics of the material obtained in the process of forming. Found that when a hydraulic forging press to form an elastic unit holds minimal medium and a more uniform thinning of the material and the strength characteristics of the material in the area of ​​the panel through the rifts hardening reaches the desired value.