Factors Affecting Almen Strip Curvature Readings

Author:  D Kirk, R Hollyoak
Source:  Conf Proc: ICSP-7 (pg 291-300)
Doc ID:  1999040
Year of Publication:  1999
Abstract:  
This study considers the actual shape of deformed Almen strips, the source of that shape, variations in strip parameters and peening vaariables affecting curvature readings. It is shown that deformed Almen strips have a shape based on three-dimensional parabolic curvature. This shape can only be induced by the generation of uniformly-distributed surface forces. Complex curvature found in clamped, peened, strips is explained in terms of hold-down bending moments. Batches of Almen strips have been found to have remarkable in-batch consistency of hardness and dimensional properties. Inter-batch variation of hardness is, however, significant. Hardness has been correlated with tensile properties. X-ray analysts showed that Almen strips do not possess crystallographic preferred orientation. The torque applied to the hold-down screws has been shown to have a small but insignificant effect on curvature readings. Air pressure variations have a much greater influence on induced curvature.