Haocheng Jiang¹, Jue Zhu^2,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.27, No.1, pp. 1-2, 2023, DOI:10.32604/icces.2023.09586

Abstract The tests of dynamic mechanical properties of materials at high temperature and high strain rate has always been a difficult issue [1]. In order to perform the dynamic mechanical properties of G550 cold-formed steel at high temperature and high strain rate, a set of Hopkinson Tension test device which can synchronize with high temperature control is developed for material test [2]. The stress-strain curves obtained from the tests were used to explore the influence of temperature and strain rate on the rheological properties of material by combining micro-analysis. The results show that G550 cold-formed steel… More >

Stepan Konev¹, Victor A. Eremeyev^2,3, Hamid M. Sedighi^4,5,*, Leonid Igumnov², Anatoly Bragov², Aleksandr Konstantinov², Ayaulym Kuanyshova¹, Ivan Sergeichev¹

CMES-Computer Modeling in Engineering & Sciences, Vol.137, No.3, pp. 2149-2161, 2023, DOI:10.32604/cmes.2023.028179 - 03 August 2023

Abstract This article presents the results of experimental studies concerning the dynamic deformation and failure of a unidirectional carbon fiber reinforced plastic (T700/LY113) under compression. The test samples were manufactured through the filament winding of flat plates. To establish the strain rate dependencies of the strength and elastic modulus of the material, dynamic tests were carried out using a drop tower, the Split Hopkinson Pressure Bar method, and standard static tests. The samples were loaded both along and perpendicular to the direction of the reinforcing fiber. The applicability of the obtained samples for static and dynamic… More >

Yubo Zhang, Ping Lei, Lina Wang, Jiqing Yang^*

Journal of Renewable Materials, Vol.11, No.1, pp. 393-410, 2023, DOI:10.32604/jrm.2022.022659 - 10 August 2022

Abstract In this paper, a split Hopkinson pressure bar (SHPB) was used to investigate the dynamic impact mechanical behavior of sisal fiber-reinforced cement-based composites (SFRCCs), and the microscopic damage evolution of the composites was analyzed by scanning electron microscopy (SEM) and energy-dispersive X-ray spectrometry (EDS). The results show that the addition of sisal fibers improves the impact resistance of cement-based composite materials. Compared with ordinary cement-based composites (OCCs), the SFRCCs demonstrate higher post-peak strength, ductility, and energy absorption capacity with higher fiber content. Moreover, the SFRCCs are strain rate sensitive materials, and their peak stress, ultimate More >

Daniel Varadaradjou^1,*, Hocine Kebir¹, Jérôme Mespoulet², David Tingaud³, Salima Bouvier¹, Paul Deconick², Kei Ameyama⁴, Guy Dirras^3,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.24, No.1, pp. 1-3, 2022, DOI:10.32604/icces.2022.08673

Abstract The development of new architecture metallic alloys with controlled microstructures is one of the strategic ways for designing materials with high innovation potential and, particularly with improved mechanical properties as required for structural materials [1]. Indeed, unlike conventional counterparts, metallic materials having so-called harmonic structure displays strength and ductility synergy. The latter occurs due to a unique microstructure design: a coarse grain structure surrounded by a 3D continuous network of ultra-fine grain known as “core” and “shell”, respectively. In the present study, pure harmonic-structured (HS) Nickel samples were processed via controlled mechanical milling and followed… More >

Xiaoxia Liu^1,2,*

CMES-Computer Modeling in Engineering & Sciences, Vol.131, No.2, pp. 919-927, 2022, DOI:10.32604/cmes.2022.017756 - 14 March 2022

Abstract Magnesium (Mg) and its composites have been widely used in different fields, but the mechanical properties and deformation mechanisms of polycrystalline Mg (polyMg) at the atomic scale are poorly understood. In this paper, the effects of grain size, temperature, and strain rate on the tensile properties of polyMg are explored and discussed by the Molecular dynamics (MD) simulation method. The calculated results showed that there exists a critical grain size of 10 nm for the mechanical properties of polyMg. The flow stress decreases with the increase of grain size if the average grain size is… More >

Erin K. Davis¹, Salil Ginde¹, Jessica Stelter², Peter Frommelt¹, Garick D. Hill³

Congenital Heart Disease, Vol.14, No.5, pp. 720-725, 2019, DOI:10.1111/chd.12814

Abstract Background/Hypothesis/Objectives: Postoperative complications after the Fontan operation for single ventricle heart disease are common and include persistent pleural drainage and prolonged length of hospital stay (LOS). Diastolic ventricular dysfunction may increase risk for postoperative complications by raising central venous pressures. We sought to determine the relationship between preoperative echocardiographic measurements of diastolic function, including myocardial deformation imaging, on (a) preoperative invasive catheterization measurements and (b) postoperative outcomes after the Fontan procedure.
Design/Methods: All patients that underwent Fontan procedure from 2011 to 2017 were included. Echocardiograms performed within 6 months prior to Fontan operation were evaluated. Measurements of… More >

Liang Wu¹, Xiaorui Xiang¹, Yang Chen¹, Karrech Ali^2,*, Junru Zhou^1,*, Ming Chen³

CMES-Computer Modeling in Engineering & Sciences, Vol.120, No.2, pp. 421-443, 2019, DOI:10.32604/cmes.2019.05218

Abstract During the excavation of deep rock, a sudden change in boundary conditions will cause the in-situ stress on the excavation surface to release instantaneously. This disturbance propagates in the form of an unloading stress wave, which will enlarge the damage field of surrounding rock. In this paper, the dynamic unloading problem of the in-situ stress in deep rock excavation is studied using theoretical, numerical, and experimental methods. First, the dynamic unloading process of rock is analyzed through adopting the wave equation, and the equivalent viscous damping coefficient of the material is taken into consideration. Calculations More >

R. R. Valisetty¹, A. M. Dongare², A. M. Rajendran³, R. R. Namburu¹

CMC-Computers, Materials & Continua, Vol.44, No.1, pp. 23-57, 2014, DOI:10.3970/cmc.2014.044.023

Abstract Materials used in soldier protective structures, such as armor, vehicles and civil infrastructures, are being improved for performance in extreme dynamic environments. Accordingly, atomistic molecular dynamics simulations were performed to study the spall response in a single crystal aluminum atom system. A planar 9.6 picoseconds (ps) shock pulse was generated through impacts with a shock piston at velocities ranging from 0.6 km/s to 1.5 km/s in three <1,0,0>, <1,1,0>, and <1,1,1> crystal orientations. In addition to characterizing the transient spall region width and duration, the spall response was characterized interms of the traditional axial stress vs. axial… More >

R. R. Valisetty¹, A.M. Dongare², A.M. Rajendran³, R. R. Namburu¹

CMC-Computers, Materials & Continua, Vol.36, No.3, pp. 231-255, 2013, DOI:10.3970/cmc.2013.036.231

Abstract Materials used in soldier protective structures, such as armor, vehicles and civil infrastructures, are being improved for performance in extreme dynamic environments. Nanocrystalline metals show significant promise in the design of these structures with superior strengths attributed to the dislocation-based and grain-boundary-based processes as compared to their polycrystalline counterparts. An optimization of these materials, however, requires a fundamental understanding of damage evolution at the atomic level. Accordingly, atomistic molecular dynamics simulations are performed using an embedded-atom method (EAM) potential on three nano-crystalline aluminum atom systems, one a Voronoi-based nano-crystalline system with an average grain size More >

H.H. Luo¹, Z.H. Tan^1,2, X. Han¹, C. Chen¹

CMC-Computers, Materials & Continua, Vol.32, No.1, pp. 1-14, 2012, DOI:10.3970/cmc.2012.032.001

Abstract The dynamic properties of aluminium alloy foam were investigated by using split Hopkinson pressure bar (SHPB) with diameter of 40 mm. The aluminium alloy pressure bar and pulse shape technique were used to modify the traditional SHPB due to the low impedance of aluminium alloy foam. Wave dispersion correction on the aluminium alloy pressure bar was studied by Fourier series. And the finite element numerical simulation was also performed to demonstrate and validate the dispersion correction results by Fourier series method. The reflected and transmitted wave measured in SHPB experiments were corrected by the backward More >