Syntactic Foam Prepared with Glass Hollow Spheres of Designed Size and Wall Thickness Ratio

2014 ◽  
Vol 1061-1062 ◽  
pp. 129-132
Author(s):  
Zhuo Chen ◽  
Zhi Xiong Huang ◽  
Bing Yan Jiang

A new type of syntactic foam fabricated with four types of hollow microspheres (HGMs) were prepared and its compressive properties were tested following ASTM D 695-96 standard. The HGMs were designed to have specific size distribution and wall thickness. The compressive strength and modulus of the new syntactic foam were compared with those prepared with single type of HGMs. With same density, the new syntactic foam have better compressive properties.

2013 ◽  
Vol 701 ◽  
pp. 291-295
Author(s):  
Norwanis Hasan ◽  
Syed Fuad Saiyid Hashim ◽  
Zulkifli Mohamad Ariff

An innovative technique in producing cement syntactic foam (CSF) was proposed in this investigation. This cellular composite material basically consists of a cement matrix embedded with in-house developed cement hollow spheres (CHS). The produced foams incorporated with CHS having different wall thickness, were characterized for compressive strength and then compared with that of plain cement. It was observed that the CSFs were 37%-55% lighter than the plain cement but possessed compromised compressive strength. The comparative compressive properties of CSFs were also evaluated and reported. It was found that the CSF incorporated with thicker-coated CHS showed higher compressive strength compared to that of incorporated with thinner-coated CHS. The failure patterns within the test samples were also examined to determine the failure mechanism. These observations showed that both CSFs exhibited shearing type failure but exhibit different types of crack fractures due to the difference in CHS wall thickness.


2018 ◽  
Vol 280 ◽  
pp. 301-307
Author(s):  
Z. Zakaria ◽  
C.Y. Yao

This research focuses on the effect of rejected nitrile butadiene rubber (rNBR) gloves particles reinforced epoxy macrospheres (EM) on the physical properties and compressive stress of syntactic foam. Adding rNBR particles on the surface of macrospheres can increase the energy absorption as a result of improving the compressive properties of syntactic foam. Three types of macrospheres have been produced for the fabrication of syntactic foam, namely EM without rNBR, 1-layer rNBR-EM and 2-layer rNBR-EM. The results showed that increased rNBR particles layer on macrospheres has increased the wall thickness, and reduced the radius ratio of macrospheres as well as increased the density of syntactic foams. The compressive strength and modulus of syntactic foam with 2-rNBR-EM increased compared to the syntactic foams of 1-rNBR-EM and EM without rNBR. In addition, the toughness of the 2-rNBR-EM increased compared to the syntactic foams of 1-rNBR-EM and EM without rNBR.


1998 ◽  
Vol 521 ◽  
Author(s):  
M. Hartmann ◽  
K. Reindel ◽  
R. F. Singer

ABSTRACTSyntactic magnesium foams which consist of thin-walled hollow alumina spheres embedded in a magnesium matrix were fabricated by infiltrating a three-dimensional array of hollow spheres with a magnesium melt by using a gas pressure-assisted casting technique.The resulting composite contains closed cells of homogeneous and isotropic morphology. The densities of the syntactic magnesium foams were between 1.0 and 1.4 g/cm3. The densities were controlled by variations in the bulk density of the hollow spheres with the volume fraction of spheres kept constant at approximately 63 %.Compressive deformation characteristics of the composites were evaluated with respect to the influence of matrix strength and sphere wall thickness on characteristic variables such as compressive strength, plateau stress and energy absorption efficiency. Differences in the strength of the magnesium-based matrix materials investigated (cp-Mg, AM20, AM50, AZ91) had little influence on the compressive strength of the syntactic foam. However, an increasing relative wall thickness of the hollow ceramic spheres led to a significant strength enhancement. In all cases the ratio between compressive and plateau strength rose with increasing composite strength resulting in decreasing energy absorption efficiency.


2014 ◽  
Vol 809-810 ◽  
pp. 237-242
Author(s):  
Xin Jin ◽  
He Yi Ge ◽  
Ping Wang ◽  
Zhong Yuan Pan ◽  
Juan Chen

In this study, hollow glass microspheres (HGM) and hollow polystyrene microspheres (HPSM) have been employed as fillers in epoxy resin to prepare the syntactic foam. A kind of good performance composite was prepared. The effects of presence of various hollow microspheres on the impact and compressive properties of syntactic foams are studied. Weight fraction of HPSM and HGM for the syntactic foams varies up to 2.0 wt% and 25 wt%, respectively. The results show that the coupling agent can induce the interfacial adhesion between the HGM and the resin and help HGM uniformly disperse in the resin and hence result in better mechanical properties of composite. On the other hand, the effect of HPSM for the composite density is greater than that of HGM. The addition of a small percentage of HPSM helps produce an important improvement in the low density of syntactic foam. The syntactic foam has uniform stability component and the excellent integrative performances. Fabricated syntactic foams had compression strength of 51.96 MPa and density of 0.671 g/cm3.


2011 ◽  
Vol 321 ◽  
pp. 7-10 ◽  
Author(s):  
Zhuo Chen ◽  
Zhi Xiong Huang ◽  
Yan Qin ◽  
Min Xian Shi ◽  
Qi Lin Mei ◽  
...  

In this work, syntactic foams made of microballoons having same wall thickness ratio but with different particle size was prepared. Microballoons of three size distribution ranges were selected .The property of the syntactic foams were studied by quasi-static compression test. The experimental results show the microballoons size doesn’t influent the mechanical properties of the syntactic foam significantly. The failure mode of the syntactic foams was also studied in this work.


2018 ◽  
Vol 933 ◽  
pp. 174-181 ◽  
Author(s):  
Ming Ming Su ◽  
Han Wang ◽  
Kai Yan Li ◽  
Hai Hao

Metal matrix syntactic foams with relativity low density (2.03 g/cm3) were prepared by stir casting method. The syntactic foam is comprised of alumina hollow spheres with a diameter range of 1.0-1.5 mm as reinforcement and ZL111 aluminum alloy as matrix. Calcium particles are used to increase the viscosity of the melt to ensure that low density hollow spheres are immersed in the melt. Microstructure characteristics and quasi-static compressive properties of syntactic foams were studied. The hollow spheres were uniformly distributed in the aluminum matrix, and the interface between them was in continuous contact. Compressive stress-strain curve exhibits three distinct stages of deformation: (i) the linear elastic stage; (ii) the plateau area; (iii) final densification stage. The compression strength and plateau stress are 85 MPa and 75 MPa, respectively. The main reasons for the sample failure are the collapse of hollow spheres and the formation of multiple shear bands.


2014 ◽  
Vol 670-671 ◽  
pp. 630-633
Author(s):  
Zhuo Chen ◽  
Zhou Zhou ◽  
Bing Yan Jiang

This paper addresses elastic analysis based on 3D finite element model for hollow sphere structures. In finite element models, which were analyzed under pressure of 1MPa, volume fraction of hollow spheres is kept at 30%, and hollow spheres are randomly located in the matrix. Five types of hollow sphere are used to form the model. All the types of hollow spheres have 60μm particle sizes, but different wall thicknesses. A comparison in stress distribution between the hollow sphere and matrix is made, which shows that in composites containing thin-walled hollow particles the maximum stress is located in the inner surface of particle wall, whereas increasing the wall thickness of hollow spheres results in getting some part of matrix around hollow spheres involved in energy absorption. Moreover, the location of the maximum stress in matrix related closely to the spatial arrangement of the particles. The study provides an insight into the micro structural performance of syntactic foam under load.


Nanomaterials ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 1003
Author(s):  
Pantharee Kongsat ◽  
Sakprayut Sinthupinyo ◽  
Edgar A. O’Rear ◽  
Thirawudh Pongprayoon

Several types of hematite nanoparticles (α-Fe2O3) have been investigated for their effects on the structure and properties of fly ash (FA) blended cement. All synthesized nanoparticles were found to be of spherical shape, but of different particle sizes ranging from 10 to 195 nm depending on the surfactant used in their preparation. The cement hydration with time showed 1.0% α-Fe2O3 nanoparticles are effective accelerators for FA blended cement. Moreover, adding α-Fe2O3 nanoparticles in FA blended cement enhanced the compressive strength and workability of cement. Nanoparticle size and size distribution were important for optimal filling of various size of pores within the cement structure.


Polymers ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 683
Author(s):  
Xinfeng Wu ◽  
Yuan Gao ◽  
Tao Jiang ◽  
Ying Wang ◽  
Ke Yang ◽  
...  

Because the aerogel has ultra-low density and good impact resistance, the aerogel material, epoxy-hardener system, and expandable polystyrene beads (EPS) were used to prepare the lightweight aerogel reinforced hollow epoxy macro-spheres (AR-HEMS). The multi-phase epoxy syntactic foam (ESF) was manufactured with the epoxy-hardener system, HGMS (EP-hardener-HGMS), and AR-HEMS by “the compression modeling method.” In this experiment, in order to enhance the strength of the ESF, some different kinds of the carbon fiber (CF) were added into the EP-hardener-HGMS system (CFR-EP). The influence of the volume stacking fraction, inner diameter, and layer of the AR-HEMS and the content and type of the CF in the EP-HGMS (CFR-EP) system on the compressive strength of the ESF were studied. Weighing the two factors of the density and compressive strength, the ESF reinforced by 1.5 wt% CF with 90% AR-HEMS has the better performance. This kind of the ESF has 0.428 g/cm3 nd 20.76 Mpa, which could be applied in 2076 m deep sea.


Minerals ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 714 ◽  
Author(s):  
Evangelos Petrakis ◽  
Vasiliki Karmali ◽  
Georgios Bartzas ◽  
Konstantinos Komnitsas

This study aims to model grinding of a Polish ferronickel slag and evaluate the particle size distributions (PSDs) of the products obtained after different grinding times. Then, selected products were alkali activated in order to investigate the effect of particle size on the compressive strength of the produced alkali activated materials (AAMs). Other parameters affecting alkali activation, i.e., temperature, curing, and ageing time were also examined. Among the different mathematical models used to simulate the particle size distribution, Rosin–Rammler (RR) was found to be the most suitable. When piecewise regression analysis was applied to experimental data it was found that the particle size distribution of the slag products exhibits multifractal character. In addition, grinding of slag exhibits non-first-order behavior and the reduction rate of each size is time dependent. The grinding rate and consequently the grinding efficiency increases when the particle size increases, but drops sharply near zero after prolonged grinding periods. Regarding alkali activation, it is deduced that among the parameters studied, particle size (and the respective specific surface area) of the raw slag product and curing temperature have the most noticeable impact on the compressive strength of the produced AAMs.


Sign in / Sign up

Export Citation Format

Share Document