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Quasistatic deformation analysis of melt‑based molded die‑cast open‑cell aluminum alloy foam

Raza Mohammad Shahid, Datta Susmita, Saha Partha

Archives of Civil and Mechanical Engineering

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2023

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Vol. 23, no. 1

art. no. e24, 2023

EN

The metal foams behavior significantly depends on the method applied for its manufacturing. Present work investigates the mechanical quasistatic three-point and compressive deformation behavior of molded die-cast open-cell Aluminum Alloy foam (OCAF). Different span lengths and loading velocities were selected for the experimentation. The deformation behavior of the OCAF was studied and the effect was correlated with different theories available for foam deformation. The plastic behavior of OCAF was also studied using a compression loading-unloading experiment at different stress and strain values. Microstructural study and phase analysis were carried out at the cell wall surfaces using fractography to establish the cause of brittle failure dominant in the foam. Further, micro-CT analysis was used to study the cell deformation in the bulk material and the role of micropores and macro-pores.

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A New Testing Method for the Mechanical Properties of Elastic Explosive Compositions

Powała Dorota, Nita Marcin, Orzechowski Andrzej, Maranda Andrzej

Central European Journal of Energetic Materials

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2021

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Vol. 18, no. 4

545--569

EN

In recent years, Polymer Bonded Explosives (PBX) have been used in a wide variety of military applications. Many different kinds of polymers are used for such explosive formulations. This component determines both the preparation method and the properties of a PBX. In this paper, results are presented of studies on the preparation and testing of explosive compositions based on pentaerythritol tetranitrate (PETN, penthrite) and silicone rubber. These studies were undertaken to obtain elastic formulations of PBXs. Therefore, the possibility of applying a silicone rubber as a component of the composition was checked. In the first stage of this study, several compositions were prepared in order to choose the optimal mixture ratio with respect to cohesion of the explosive. For this purpose, a new method using the Brookfield Texture Analyser was developed. Subsequently, compatibility tests using thermal analysis methods were carried out. The best of composition was subjected to tests for determining its physicochemical and explosive characteristics.

3

Compression testing of flanged and conical specimens

Abdul-Rahman M., Raddad B.

Prace Naukowe Politechniki Warszawskiej. Mechanika

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2005

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z. 207

165--170

EN

Compression testing of flanged and tapered specimens can provide the small regions of the fracture localization. In this work, analysis of compression of three specimens for low carbon steel, aluminum alloy containing 4% copper and 60/40 brass have been carried out. Typical stress/strain curves have been presented for the different materials. Effect of the initial H0/D0 ratio and other dimensional factors heve been investigated. Fracture modes for the different specimen geometries have been also detected.