Effect of Pulse-Reverse Current on Microstructure and Properties of Electroformed Nickel–Iron Mold Insert

In the paper, a theoretical investigation was presented, which is used to explain the effect of pulse-reverse current on uniformity in micro-electroforming. And micro-electroforming experiments of two different pulse-reverse currents with gaps in positive direction were carried out correspondingly. The mold inserts used in micro fluidic-chip were micro-electroformed in these experiments, and its feature width is 90um. No backing process was adopted, which mainly consisted of three procedures. Two different pulse-reverse currents used in these experiments were pulse-reverse current with gaps in both positive and negative direction, and pulse-reverse current with gaps only in positive direction, respectively. The fundamental parameters of these experiments were summarized from lots of micro-electroforming experiments of pulse current. After experiments, comparisons were carried out between the results of pulse-reverse current experiments and pulse current experiment. Because negative current could erode the tips on electroforming surface, better uniformity was obtained in these experiments using pulse-reverse currents. The experimental results were consistent with the theoretical investigation.

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Fabrication of thin copper mesh for electromagnetic interference of display panel by pulse reverse current method and study on the microstructure by small angle neutron scattering

Metals and Materials International ◽

10.1007/s12540-012-5014-7 ◽

2012 ◽

Vol 18 (5) ◽

pp. 839-843 ◽

Cited By ~ 1

Author(s):

Man Kim ◽

Joo-Yul Lee ◽

Yong Choi

Keyword(s):

Neutron Scattering ◽

Small Angle ◽

Electromagnetic Interference ◽

Small Angle Neutron Scattering ◽

Reverse Current ◽

Current Method ◽

Pulse Reverse ◽

Copper Mesh

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Electrical contact performance of various electro-deposited graphene reinforced silver-based nanocomposites

Materials Testing ◽

10.1515/mt-2020-620412 ◽

2020 ◽

Vol 62 (4) ◽

pp. 401-407

Author(s):

Ramazan Karslioglu ◽

Lujain Al-Falahi

Keyword(s):

Pulse Current ◽

Electrical Contact ◽

Reverse Current ◽

Electrical Contacts ◽

Test Device ◽

Arc Erosion ◽

Contact Test ◽

Grain Sizes ◽

Contact Erosion ◽

Pulse Reverse

Abstract Silver and silver(Ag)-graphene(Gr) nanocomposite coatings were prepared via direct current, pulse current and pulse reverse current on copper electrical contacts for evaluating electrical contact performance. The effects of the addition of Gr and current types on microstructure, crystallographic orientation, mechanical properties and electrical contact performance were investigataed via a scanning electron microscope, an X-Ray diffractometer, microhardness test device and an electrical contact test device, respectively. The addition of Gr changed the Ag surface morphology and decreased grain sizes. Moreover, the addition of Gr significantly improved arc erosion resistivity and decreased the average working temperature during the contact test. In addition, pulse current and pulse reverse current provided a significant improvement in microhardness and electrical contact erosion resistance owing to increased embedded graphene amounts in silver layers.

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