Method for testing expansion and contraction of circuit board

The invention discloses an expansion and shrinkage test method of a circuit board. The method comprises the following steps: obtaining theoretical processing data of a test copper-clad plate; processing a test copper-clad plate based on the theoretical processing data, and obtaining actual processing data of the test copper-clad plate; obtaining expansion and contraction data of the tested copper-clad plate by using the theoretical processing data and the actual processing data; and acquiring the local maximum allowable deformation of the tested copper-clad plate based on the theoretical processing data, the actual processing data and the expansion and contraction data. According to the method, the local expansion and shrinkage condition of the plate can be quantified through the local maximum allowable deformation, so that the plate is prevented from flowing into the subsequent process under the condition that the local deformation is serious, and the scrap cost is reduced. 本申请公开了一种线路板的涨缩测试方法，包括：获取到测试覆铜板的理论加