Editing Syntactic foam (section)

==Applications==
[[File:Syntactic foam sphere.jpg|thumb|Syntactic foam sphere used as a subsurface float in [[Mooring (oceanography)|oceanographic mooring]].]]
Current applications for syntactic foam include buoyancy modules for [[marine riser tensioner]]s, [[remotely operated underwater vehicle]]s (ROVs), [[autonomous underwater vehicle]]s (AUVs), deep-sea exploration, [[hull (watercraft)|boat hulls]], and [[helicopter]] and [[airplane]] components.

''[[Cement]]itious'' syntactic foams have also been investigated as a potential lightweight structural composite material. These materials include glass microspheres dispersed in a ''cement'' paste matrix to achieve a closed cell foam structure, instead of a metallic or a polymeric matrix. Cementitious syntactic foams have also been tested for their mechanical performance under high strain rate loading conditions to evaluate their energy dissipation capacity in crash cushions, blast walls, etc. Under these loading conditions, the glass microspheres of the cementitious syntactic foams did not show progressive crushing. Ultimately, unlike the polymeric and metallic syntactic foams, they did not emerge as suitable materials for energy dissipation applications.<ref>{{Cite journal|date=2019-01-01|title=Strain rate-dependent compressive behavior and failure mechanism of cementitious syntactic foams|url=https://www.sciencedirect.com/science/article/abs/pii/S0958946518302713|journal=Cement and Concrete Composites|language=en|volume=95|pages=70–80|doi=10.1016/j.cemconcomp.2018.10.009|issn=0958-9465|last1=Bas|first1=Halim Kerim|last2=Jin|first2=Weihua|last3=Gupta|first3=Nikhil|last4=Luong|first4=Dung D.|s2cid=139598037|url-access=subscription}}</ref> Structural applications of syntactic foams include use as the intermediate layer (that is, the core) of [[sandwich panel]]s.

Though the cementitious syntactic foams demonstrate superior specific strength values in comparison to most conventional cementitious materials, it is challenging to manufacture them. Generally, the hollow inclusions tend to buoy and segregate in the low shear strength and high-density fresh cement paste. Therefore, maintaining a uniform microstructure across the material must be achieved through a strict control of the composite [[rheology]].<ref>{{Cite journal|date=2018-07-01|title=In-situ micro-CT characterization of mechanical properties and failure mechanism of cementitious syntactic foams|url=https://www.sciencedirect.com/science/article/abs/pii/S0958946517303323|journal=Cement and Concrete Composites|language=en|volume=90|pages=50–60|doi=10.1016/j.cemconcomp.2018.03.007|issn=0958-9465|last1=Bas|first1=Halim Kerim|last2=Jin|first2=Weihua|last3=Gupta|first3=Nikhil|last4=Behera|first4=Rakesh Kumar|s2cid=140068274|url-access=subscription}}</ref> In addition, certain glass types of microspheres may lead to an [[Alkali–silica reaction|alkali silica reaction]]. Therefore, the adverse effects of this reaction must be considered and addressed to ensure the long-term durability of these composites.<ref>{{Cite journal|date=2021-04-01|title=Chemical stability of hollow glass microspheres in cementitious syntactic foams|url=https://www.sciencedirect.com/science/article/abs/pii/S0958946520304327|journal=Cement and Concrete Composites|language=en|volume=118|pages=103928|doi=10.1016/j.cemconcomp.2020.103928|issn=0958-9465|last1=Bas|first1=Halim Kerim|last2=Jin|first2=Weihua|last3=Gupta|first3=Nikhil|s2cid=234059434|url-access=subscription}}</ref>

Other applications include;
*Deep-sea buoyancy foams. A method of creating submarine hulls by [[3D printing]] was developed in 2018.<ref>{{Cite web|url=https://engineering.nyu.edu/news/3-d-printing-breakthrough-lightweight-syntactic-foams-could-help-submarines-dive-deeper|title=3-D Printing Breakthrough for Lightweight Syntactic Foams Could Help Submarines Dive Deeper {{!}} NYU Tandon School of Engineering|website=engineering.nyu.edu |date=February 6, 2018 |language=en|access-date=2018-09-22}}</ref>
*Thermoforming plug assist
*Radar transparent materials
*Acoustically attenuating materials
*Cores for [[sandwich composite]]s<ref>{{cite journal |first1=Md Mainul |last1=Islam |first2=Ho Sung |last2=Kim |title=Sandwich composites made of syntactic foam core and paper skin: manufacturing and mechanical behavior |journal=Journal of Sandwich Structures and Materials |date=2012 |volume=14 |issue=1 |pages=111–127 |doi=10.1177/1099636211413564|s2cid=135970284 }}</ref><ref>{{cite journal |first1=Md |last1=Arifuzzaman |first2=Ho Sung |last2=Kim |title=Novel flexural behaviour of sandwich structures made of perlite foam/sodium silicate core and paper skin |journal=Construction and Building Materials |volume=148 |date=1 September 2017 |pages=321–333 |doi=10.1016/j.conbuildmat.2017.05.073}}</ref>
*Blast mitigating materials
*Sporting goods such as bowling balls, tennis rackets, and [[soccer ball]]s.<ref name=lm6>{{dead link|date=July 2015}}{{Cite web|url=http://www.cefic.be/templates/shwNewsFull.asp?NSID=543&HID=2&P=7|title=Performing Plastics - How plastics set out to conquer the world of sports|access-date=2009-08-10|publisher=European Chemical Industry Council|date=3 February 2005|first=Johann|last=Thim}}{{Dead link|date=June 2018 |bot=InternetArchiveBot |fix-attempted=no }}</ref>