METHOD FOR MEASURING RESIDUAL STRESS IN THIN PLATE

Provided is a method for measuring residual stress in a thin plate. The method includes: S1: prearranging and cutting a plurality of fins that have the same length and are parallel to a length direction of the thin plate at equal intervals in a width direction of the thin plate, where the fins have fixed ends and movable ends, computing x-direction strain εi0 and x-direction residual stress σi0 in the length direction of the thin plate borne by each fin according to lengths of each fin before and after cutting, and obtaining distribution of x-direction residual stress in the width direction of the thin plate according to all σi0; S2: repeatedly cutting the fixed ends in a thickness direction of the thin plate, computing a total cutting depth Zij and x-direction residual stress σij of each fin after each cutting, and obtaining distribution of x-direction residual stress in the thickness direction of the thin plate borne by an ith fin according to all σij; and S3: computing distribution σx, σx = σi0 + σij, of x-direction residual stress on a yz cross section of the thin plate according to σi0 obtained in S1 and corresponding σij in S2. According to this solution, a distribution rule of the residual stress in a thickness of the thin plate is quantitatively characterized.