An Innovative Fabrication Process of Porous Metal Fiber Sintered Felts with Three-Dimensional Reticulated Structure

Abstract

A novel porous metal fiber sintered felt (PMFSF) with a three-dimensional reticulated structure has been produced by the solid-state sintering of copper fibers. The copper fibers, with several microstructures distributed onto the surface, were fabricated using the cutting method. The Scanning Electron Microscope (SEM) results revealed that there were two kinds of sintering joints present in the PMFSFs: fiber-to-fiber surface contact and crossing fiber meshing. In the sintering process, the surface microstructures of the fibers helped to improve the forming process of the PMFSFs, as a result of high surface energy. Furthermore, the effect of different sintering parameters on the forming process of the PMFSFs was studied in detail, including the sintering temperature and holding time. The sintering temperatures had a significant influence on the surface microstructures of single fiber and specific surface area of the PMFSFs, but the holding time did not. The optimal PMFSF with a three-dimensional reticulated structure and larger specific surface area was produced by sintering copper fibers at 800 C for 30 minutes in the reduction atmosphere.Keywords Copper fiber; Metal fiber sintered felt; Porous metal; Sintering. IntroductionPorous metal material, an interesting engineering material with excellent performances, is being explored due to its porous structure and unique properties. In recent years, porous metal materials have been widely used in aerospace, metallurgic, mechanic, petrochemical, energy, pharmaceutical, architectural, and transportation fields [1][2][3][4][5]. Porous metal fiber sintered felts (PMFSFs), made from metal fibers, attract increasing attention, because of their three-dimensional reticulated structure, interconnected pores, high porosity, and large specific surface area [6][7][8]. These structural characteristics create potential to overcome the shortfalls of other porous materials. For example, porous organic polymer materials have low intensity and cannot withstand high temperature; porous ceramics have poor brittleness and bad thermal shock resistance; metal wire mesh are easily destroyed and plugged; sintered powder materials are fragile, and often fail to allow a sufficient amount of liquid to pass through. Therefore, the research related to the new type of PMFSF helps to enrich the entire system of porous metal materials. As part of a new generation of high-performance structural and functional materials, the PMFSFs have been widely used in many fields, including catalyst supports [9][10][11]

Experimental Study On The Heat Transfer Performance Of Porous Metal Fiber Sintered Sheet

“…4. As shown in the previous work [15], we could found that there were two kinds of sintering joints present in the PMFSS including point to point contact and fiber to fiber surface contact. And these two kinds of sintering joints formed two kinds of pore structures; they are point pore structure and long strip pore structure, as shown in Fig.4a and 4b, respectively.…”

Experimental investigation on the thermal performance of a heat sink filled with porous metal fiber sintered felt/paraffin composite phase change material

“…The PMFSF was manufactured in four steps [34]: (1) As shown in Fig. 3 (a), the continuous copper fibers with an equivalent diameter of 150 lm were fabricated by cutting with a multi-tooth tool.…”

“…However, the surface of these stainless-steel fibers were smooth, which couldn't fully promote the heat communication between PCM and the fibers. The copper fibers fabricated by cutting with a multi-tooth tool [34] have a large number of antler microstructures on their surface. These surface microstructures help enlarge the specific surface area of the PMFSF and accelerate the turbulent flow of liquid PCM, both of which enhance the thermal communication between PCM and PMFSF.…”

Investigation of transport property of fibrous media: 3D virtual modeling and permeability calculation

“…In addition, the porosity of PMFSS is known in advance during manufacture using the mass-volume method as follows [1]:…”

“…Porous Metal Fiber Sintered Sheet (PMFSS), a new kind of functional porous material, has been successfully produced recently and proved to be promising [1]. It has interconnected high porosity, large specific surface, and good mechanical strength [2].…”