Laser bending for adjusting curvatures of hard disk suspensions

The purpose of this work is to use 3D finite element analyses to compute bending of a hard disk suspension using a laser. The pitch and roll of the suspension can be precisely adjusted by producing a controlled amount of residual strain using the laser as a heat source. In the computational model, an uncoupled thermo-mechanical analysis is applied to calculate the laser induced thermal loading and mechanical deformation. The relation between suspension bending and laser parameters is studied based on extensive simulations. Bending resolution as high as 0.01° can be achieved. In addition, a data table is established where laser parameters, such as laser power and laser scan length can be found to correct a given pitch and roll of a hard disk suspension. Effects of uncertainties, such as sample thickness and material yield strength are also studied.