Fabrication and Mechanical Properties of Open‐Cell Austenitic Stainless Steel Foam by Electrostatic Powder Spraying Process

Abstract

An open‐cell metallic foam is newly manufactured using the electrostatic powder spraying (EPS) process, and its room temperature compressive and energy absorption properties are investigated. EPS is a process that uses electrostatic forces. The powder is negatively charged by applying direct current high voltage and undergoes electrostatic spraying on a positively charged polyurethane pre‐form. To control relative density (ρ*/ρ), three different spray amounts are applied (2.5, 3.5, and 4.5 kg m−2). Also, the relative density is measured to increase constantly with the spray amount. The room temperature compressive curves of the EPS foams represent the typical compressive stages (linear elastic, plastic collapse, and densification) of metallic foam. The plateau strengths of the EPS foams measure 0.48 MPa (spraying amount: 2.5 kg m−2), 0.76 MPa (spraying amount: 3.5 kg m−2), and 1.23 MPa (spraying amount: 4.5 kg m−2), respectively. Also, EPS 316L foam with the smallest spray amount has a lower energy absorption amount compared with other types of foam. This study also discusses the compressive and energy absorption behaviors of an open‐cell metallic foam manufactured using the EPS process in relation to its structural and microstructural characteristics.

X‐ray Tomography and Tomoscopy on Metals: A Review

“…[ 187 ] Close‐cell metal foams are produced following either the powder metallurgical route or the melt route, [ 186 ] while open‐cell foams are made by modifying close‐cell foam after foaming or by coating a polymeric precursor. [ 188 ] Using space holders [ 189 ] or replication [ 190 ] methods is another option to manufacture a more general class of cellular structures that differ from foams by their morphology. [ 185 ] In recent years, metal foaming technology has been commercialised on a small scale.…”

“…[ 201 ] Kang et al produced and studied the mechanical properties of open‐cell austenitic stainless steel foams. [ 188 ]…”

“…[201] Kang et al produced and studied the mechanical properties of open-cell austenitic stainless steel foams. [188] Recently Wang et al studied the performance [202] and the deformation behaviour [203] under compression of aluminum alloy foams produced by the melt route. By analysing the deformation of single cells, it was possible to predict which cells are more prone to collapse during subsequent compression, as shown in Figure 10.…”

Aluminum foam development by filling architecture techniques and process optimization

“…4,5 The developed products through this technique have improved metallurgical 6,7 and mechanical properties. 8,9 In recent years, researchers have been focused on the development of foam by different techniques. 10 In this regard foamable precursor is developed with the help of FSP to check the feasibility of the process 11 and also utilized this process to improve the quality of foam produced.…”