EFFECT OF COLD FORMING ON THE FATIGUE PROPERTIES OF HY-80 STEEL PLATES

摘要

Because the cold forming of submarine-hull plates can significantly alter their mechanical properties, the Applied Research Laboratory initiated a study to determine the effect of cold deformation on the mechanical proper¬ties of 2-1/2-inch-thick plates of HY-80 steel cold-formed to small radii and consequently to large surface strains.nThe present report describes the results of a limited investigation to determine the effects of cold deformation and subsequent stress relieving or aging on the rotating-beam fatigue properties of HY-80 steel. The tests were run to determine whether sufficient variation in the low-cycle fatigue lives existed to warrant an extensive investigation of the effects of cold forming on the fatigue properties of HY-80 steel.nThe results indicated that no large changes took place in the rotating-beam fatigue lives of specimens that had been previously cold deformed in tension or compression or of specimens that had been cold deformed and subsequently stress-relieved or aged, especially when compared with expected changes in fatigue life resulting from notches, flaws, etc. Thus the effects of cold deformation on the rotating-beam fatigue behavior of HY-80 steel were relatively minor.