Stress corrosion device for lap joint sample and method for monitoring critical cracking behavior of stress corrosion crack of single lap joint sample

The invention discloses a lap joint sample stress corrosion device and a method for monitoring the critical cracking behavior of a stress corrosion crack of a single lap joint sample, and the lap joint sample stress corrosion device comprises a corrosion environment box, an external force loading platform, a group of laser range finders and an external force loading platform support, laser range finders are symmetrically arranged on the external force loading platform support, the external force loading platform penetrates through the external force loading platform support and extends into the corrosion environment box, the external force loading platform is located between the two laser range finders, the external force loading platform support is fixed to the ground, and weights are arranged on the external force loading platform. The problems that the stress corrosion test is difficult to carry out on the lap joint sample and the critical cracking behavior of the stress corrosion crack of the single lap j