Measurement method of internal stress of electrical deposition layer

Abstract

The invention relates to the field of electroforming, in particular to a measurement method of the internal stress of an electrical deposition layer. The measurement method comprises the following procedures: dipping a cathode test slice and an anode test slice in a transparent electroplating bath, annealing the anode test slice for 30 to 50 min under the temperature of 600 to 800 DEG C before test to eliminate the residual stress of the anode test slice, rolling out the anode test slice under static press, making the single surface of the anode test slice insulated, measuring the elastic modulus value E and the thickness value t of the anode test slice, and calculating the length L of the anode test slice dipped in electroplating liquid; making the insulated surface of the anode test slice back to the cathode test slice, connecting the cathode test slice and the anode test slice with a power supply, providing a camera outside the transparent electroplating bath, and calculating the displacement Z' of the bottom end of the anode test slice; measuring the thickness of the electroplated anode test slice, calculating the thickness value of the electrical deposition layer, and finally, calculating the internal stress S of the electrical deposition layer according to a formula, i.e. S=(1/6)*(Et<2>Z'/dL<2>). In the invention, computer imaging and measurement technique are adopted to accurately measure the displacement of the bottom end of the anode test slice so as to qualitatively and quantificationally measure the internal stress of the electrical deposition layer.

Description

technical field [0001] The invention relates to the field of electroforming, in particular to a method for measuring internal stress of an electrodeposited layer. Background technique [0002] The internal stress of the electrodeposited layer refers to a kind of equilibrium stress inside the electrodeposited layer without external load. This stress is due to the metal lattice defects caused by some deposition factors during the electrodeposition process. Especially under the action of some metal ions and organic additives, the internal stress of the electrodeposited layer will increase significantly. There are two types of internal stress in the electrodeposited layer: macroscopic stress and microscopic stress. The macroscopic stress is manifested in electroplating a metal sheet on one side, and the metal sheet is bent due to the internal stress of the electrodeposited layer. Bending toward the anode indicates that the electrodeposited layer is subjected to tensile stress...

AI Technical Summary

Problems solved by technology

Macroscopic stress can cause bubbles, cracks, peeling and other phenomena in the electrodeposited layer during storage and use. When external forces act, it will also cause stress corrosion and reduce fatigue strength, etc.

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