Applicability of surface residual stress on the complex components of TC4 titanium alloy using X-ray testing is researched by simulating the test surface state of structure based on four points bending machine loading of titanium alloy plate specimen and high strength titanium alloy standard sample. The datum show that surface curvature and range of beta angle do not significantly affect the results. When the radial test surface inclination is larger than 20 °

the test repeatability is drastically changed

and the result is not available when more than 30°. The result cannot be applied as surface inclination is greater than 30°. The result decreases with increasing axial angle

which decreases more than 20% when axial angle is 30°.