Potassium Bromide as Space Holder for Titanium Foam Preparation

Abstract

Titanium (Ti) alloy foam was prepared by using potassium bromide (KBr) as space holder with percentage between 20 to 40 wt.%. In this work, the potential of KBr as a new space holder was determined. The Ti alloy powder and space holder were first manually mixed before being compacted using hydraulic hand press. The green compacts were then sintered at temperature of 1160°C, 1200°C and 1240°C in a tube furnace. The microstructure of the Ti alloy foams were observed by Scanning Electron Microscope (SEM). It was revealed that the porosity content in the Ti foam was in the range of 16% to 31% and density in the range of 1.5 g/cm3 to 2.6 g/cm3. Moreover, the pore size of the titanium alloy foam is in the range of 187μm to 303μm. Although the sintering temperatures were found incapable of promoting overall densification to the Ti alloy foam, 1200°C was denoted to be the maximal temperature for promoting maximal porosity to the Ti alloy foam. Nonetheless, KBr was proven to be suitable as space holder for Ti foam preparation as referred to its stability and insolubility in the Ti alloy.

Investigating the mechanical properties of stainless steel foams produced by dissolving spherical urea particles as a space holder

“…Two types of space holder can be used for making open cell foam: one that evaporative materials such as ammonium bicarbonate [12], tropical starch [13], saccharose [14] magnesium [15,16]. Another leachable space holder such as NaCl [16], carbamide [17] and potassium bromide [18] have been used. Many researchers synthesized stainless steel and other metal foam using urea granules as space holder and applied leachable technique before sintering [19,20].…”