Experimental Study on the Relationship between Dislocation Density and Internal Stress in Micro Electroforming Layer

Abstract:

In the micro electroforming process, the existence of electroforming layer defects caused by macro internal stress seriously limits the application and development of the micro electroforming technology. Currently, some studies have shown that ultrasonic can reduce the internal stress. But the formation process of the internal stress and the mechanism of ultrasonic stress relief in micro electroforming layer are still unclear now. In this paper, the relationship between dislocation density and internal stress under ultrasonic was studied. The results show that the ultrasonic can make the dislocation density increase and the compressive stress decrease. When the ultrasonic power is 200W, the dislocation density and the compressive stress culminate 3.8×10^-15m^-2 and-144.4MPa, respectively. The ultrasonic can excite the movement of dislocation proliferation, pile-up and opening, which leads to a micro plastic deformation in the crystal, and thereby releases the internal stress.

• Periodical: Key Engineering Materials (Volumes 645-646)
• Pages: 405-410
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.645-646.405
• Online since: May 2015
• Authors: Chang Song, Li Qun Du*, Tong Yang, Lei Luo, You Sheng Tao, Xi Zhang
• Keywords: Dislocation Density, Dislocation Theory, Internal Stress, Ultrasonic

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