Nanoclay and Microballoons Wall Thickness Effect on Dynamic Properties of Syntactic Foam

2009 ◽  
Vol 131 (2) ◽  
Author(s):  
Sameer L. Peter ◽  
Eyassu Woldesenbet
Keyword(s):  
High Strain Rate ◽  
Strain Rate ◽  
Wall Thickness ◽  
Strain Energy ◽  
High Strain ◽  
Volume Fraction ◽  
Dynamic Properties ◽  
Syntactic Foam ◽  
Syntactic Foams ◽  
Composite Foams

The effect of nanoclay on the high strain rate mechanical properties of syntactic foams is studied. Two types of microballoons with different wall thicknesses are used in fabrication of plain and nanoclay syntactic foams. Plain syntactic foams are fabricated with 60% volume fraction of glass microballoons. 1%, 2%, and 5% volume fractions of Nanomer I.30E nanoclay are incorporated to produce nanoclay syntactic foams. High strain rate test using split Hopkinson pressure bar (SHPB) apparatus is performed on all types of plain and nanoclay syntactic foams. Dynamic modulus, strength, and corresponding strain are calculated using the SHPB data. Quasistatic test is also performed and results are compared with the dynamic SHPB results. The results demonstrate the importance of nanoclay and microballoon wall thickness in determination of syntactic foam dynamic properties. It is found that at a high strain rate, the strength and modulus of composite foams having K46 microballoons increase due to addition of 1% volume fraction of nanoclay. However, in composite foams having S22 microballoons, the increase in strength is not significant at a high strain rate. Further increase in nanoclay volume fraction to 2% and 5% reduces the strength and modulus of composite foams having S22 microballoons. Difference in wall thickness of microballoons is found to affect the strength, modulus, strain energy, and deformation of composite foams. Composite foams fabricated with thicker walled microballoons (K46) show comparatively higher values of strength, modulus, and strain energy compared with thin walled (S22) microballoons. Scanning electron microscopy shows that crack propagation behavior is distinct at different strain rates.

scholarly journals Study of the Dynamic Recrystallization Process of the Inconel625 Alloy at a High Strain Rate

Materials ◽  
2019 ◽  
Vol 12 (3) ◽  
pp. 510 ◽  
Author(s):  
Zhi Jia ◽  
Zexi Gao ◽  
Jinjin Ji ◽  
Dexue Liu ◽  
Tingbiao Guo ◽  
...  
Keyword(s):  
Dynamic Recrystallization ◽  
High Strain Rate ◽  
Strain Rate ◽  
High Strain ◽  
Volume Fraction ◽  
Electron Backscatter Diffraction ◽  
Texture Evolution ◽  
True Strain ◽  
Recrystallization Process ◽  
Compression Process

High-temperature compression and electron backscatter diffraction (EBSD) techniques were used in a systematic investigation of the dynamic recrystallization (DRX) behavior and texture evolution of the Inconel625 alloy. The true stress–true strain curves and the constitutive equation of Inconel625 were obtained at temperatures ranging from 900 to 1200 °C and strain rates of 10, 1, 0.1, and 0.01 s−1. The adiabatic heating effect was observed during the hot compression process. At a high strain rate, as the temperature increased, the grains initially refined and then grew, and the proportion of high-angle grain boundaries increased. The volume fraction of the dynamic recrystallization increased. Most of the grains were randomly distributed and the proportion of recrystallized texture components first increased and then decreased. Complete dynamic recrystallization occurred at 1100 °C, where the recrystallized volume fraction and the random distribution ratios of grains reached a maximum. This study indicated that the dynamic recrystallization mechanism of the Inconel625 alloy at a high strain rate included continuous dynamic recrystallization with subgrain merging and rotation, and discontinuous dynamic recrystallization with bulging grain boundary induced by twinning. The latter mechanism was less dominant.

High Strain Rate Tensile and Compressive Testing and Performance of Mesoporous Invar (FeNi36) Matrix Syntactic Foams Produced by Feedstock Extrusion

2016 ◽  
Vol 19 (11) ◽  
pp. 1600474 ◽  
Author(s):  
Lorenzo Peroni ◽  
Martina Scapin ◽  
Dirk Lehmhus ◽  
Joachim Baumeister ◽  
Matthias Busse ◽  
...  
Keyword(s):  
High Strain Rate ◽  
Strain Rate ◽  
High Strain ◽  
Syntactic Foams ◽  
Compressive Testing ◽  
And Performance

Effect of hollow sphere size and size distribution on the quasi-static and high strain rate compressive properties of Al-A380–Al2O3 syntactic foams

2013 ◽  
Vol 49 (3) ◽  
pp. 1267-1278 ◽  
Author(s):  
Joseph A. Santa Maria ◽  
Benjamin F. Schultz ◽  
J. B. Ferguson ◽  
Nikhil Gupta ◽  
Pradeep K. Rohatgi
Keyword(s):  
High Strain Rate ◽  
Strain Rate ◽  
Size Distribution ◽  
Hollow Sphere ◽  
High Strain ◽  
Syntactic Foams ◽  
Compressive Properties ◽  
Sphere Size

scholarly journals Structural Damages in Syntactic Metal Foams Caused by Monotone or Cyclic Compression

2017 ◽  
Vol 61 (2) ◽  
pp. 146 ◽  
Author(s):  
Bálint Katona ◽  
Imre Norbert Orbulov
Keyword(s):  
High Strain Rate ◽  
Strain Rate ◽  
Metal Matrix ◽  
High Strain ◽  
Hollow Spheres ◽  
Syntactic Foams ◽  
Pressure Infiltration ◽  
Cyclic Compression ◽  
Significant Difference ◽  
Strain Rate Compression

Closed cell, high strength metallic foams, like ceramic hollow spheres filled metal matrix foams are promising materials to build lightweight but high specific strength structural parts. The aim of this study is to investigate the damage of the foam structure during monotone or cyclic compression. The tested metal matrix syntactic foams were produced by inert gas pressure infiltration. Four different alloys as matrix and two different ceramic hollow spheres as filler material were applied. The cylindrical specimens were investigated in quasi-static and high strain rate compression and in cyclic compression. The higher strain rates were ensured by a Split-Hopkinson pressure bar system, while the fatigue tests were performed on a closed loop universal hydraulic testing machine. The failure modes of the foams have explicit differences showing barreling and shearing in the case of quasi-static and high strain rate compression respectively. In the case of the fatigue loading, there was a significant difference between the damage mechanisms of the unalloyed and the Si alloyed matrix syntactic foams. This can be explained by the difference between the yield strength of the matrix material and the ceramics hollow spheres.

Study of the Microstructure of AZ31B Magnesium Alloy under High Strain Rate Deformation

2011 ◽  
Vol 686 ◽  
pp. 325-331 ◽  
Author(s):  
Ping Li Mao ◽  
Zheng Liu ◽  
Chang Yi Wang ◽  
Zhi Wang
Keyword(s):  
Magnesium Alloy ◽  
High Strain Rate ◽  
Strain Rate ◽  
High Strain ◽  
Volume Fraction ◽  
Split Hopkinson Pressure Bar ◽  
Prismatic Slip ◽  
Hopkinson Pressure Bar ◽  
Az31b Magnesium Alloy ◽  
High Strain Rate Deformation

In order to investigate the microstructure evolution under high strain rate deformation of magnesium alloy, AZ31B magnesium alloy was impacted by Split Hopkinson Pressure Bar within the strain rates of 496s-1 to 2120s-1, then the specimens were observed by optical microscopy. The results show that when the strain rate are relatively low (496s-1-964s-1), the microstructure is predominated by high density of twinning, while increase the strain rate to 2120s-1 the volume fraction of twins is decreased. This implies that at relatively lower strain rate the deformation mechanism of AZ31B magnesium alloy under impact loading is twinning; increasing the strain rate the prismatic slip and pyramidal slip may be active besides twinning.

High strain rate compression of cenosphere-pure aluminum syntactic foams

2007 ◽  
Vol 57 (10) ◽  
pp. 945-948 ◽  
Author(s):  
Z.Y. Dou ◽  
L.T. Jiang ◽  
G.H. Wu ◽  
Q. Zhang ◽  
Z.Y. Xiu ◽  
...  
Keyword(s):  
High Strain Rate ◽  
Strain Rate ◽  
High Strain ◽  
Pure Aluminum ◽  
Syntactic Foams ◽  
Strain Rate Compression
Sign in / Sign up

Export Citation Format

Share Document