Forming mechanism of radial V-shaped microgrooves on plate using step punching method

Xiang Jian-Hua,Duan Ji-An,Liu Gui-Yun,Chen Cong-Gui,Zhou Chao,Zhang Chun-Liang

doi:10.1177/1687814014568492

Abstract

The finned surface can increase the specific surface area, which could enhance the boiling efficiency of the working medium to realize the enhancement of heat transfer performance. This research adopted a step punching method to form a radial microgroove structure on the surface of a copper plate. The scanning electron microscopy analysis indicates that when the pressed metal is in the deformation range, it will flow under extrusion and is subject to the reaction force from the metal outside the deformation range, so a micro-finned structure nearby the punching tool is formed. And the deformation area of the formed microgroove is higher than the workpiece’s primitive surface. The relationships of the punching interference length Li with θc, ac, and αpt are analyzed; and the influence of forming parameters on the groove surface morphology as well as the relationships among these parameters are discussed. When the punching depth ac is 0.3 mm and the punching feeding angle θc is 2°–4°, the finned surface of the radial V-shaped microgrooves can be obtained.

Highlights

With the increase in the micro/optoelectronic device’s power and integration, the thermal power of per unit volume is increased causing a rapid rise in heat flux
The article adopted a punching method to form a boiling structure which is composed of the radial microgrooves at the base of finned surface
Step punching process can be used to realize the forming of the radial microgroove structure

Summary

Introduction

With the increase in the micro/optoelectronic device’s power and integration, the thermal power of per unit volume is increased causing a rapid rise in heat flux. The traditional heat dissipation through finned metal surface is unable to meet the requirements of heat dissipation, and a new demand for high-efficiency heat transfer technology has been presented. A two-phase flow heat transfer thermal module with high heat transfer efficiency can effectively decrease the temperature of high-power heat sources in smaller areas.[1] Comparing finned surface with common smooth surface structure, both the heat transfer area and heat dissipation efficiency are increased for the former under the same conditions.[2,3] This kind of structure using a finned surface to improve the heat transfer performance is called surface functional structure

Methods

Results

Conclusion