Cement is one of the mostly used construction materials due to its high durability and low cost, but it suffers from brittle fracture and facile crack initiation. This article describes the use of naturally-derived renewable cellulose nanofibers (CNFs) to reinforce cement. The effects of CNFs on the mechanical properties, degree of hydration (DOH), and microstructure of cement pastes have been ...

for leucite using natural minera} potash feldspar as the major raw material, followed by bal) milling. A sintered leucite body with a 99.0% re)atiye density was obtained by heating the leucite powder cylindrical pellet at 12500C for 1 h. The mechanical properties of this dense teucite body were determined. The bending strength, fracture toughness, e)astic modulus and Vickers hardness of the bod...

An area of interest in the modern age is the human migration from rural areas to cities. Cities are characterized by a dense concentration of buildings and key infrastructures. However, what has been lacking is a pervasive sensor technology that can monitor the performance of these structures. Partly, this is due to the fact that the information collected from sensors cannot be easily transport...

The goal of the present research is to develop a better understanding of the tensile response of open-cellular aluminum 6061 T6 alloy. Both tensile and compression samples of this metallic foam were tested under constant strain rate conditions at 293, 423, and 523 K. Scanning electron microscopy was performed on individual struts to assess the modes and mechanisms associated with fracture. Theo...

Using the spark plasma sintering (SPS) method, hydroxyapatite (HAp) material was densified using a hydroxyapatite powder (RND Korea, 45 μm, purity 98 +%). The HAp was nearly completely dense with a relative density of up to 97 % after the simultaneous application of 60 MPa of pressure and about 30 minutes of electric current without significant change in the grain size. The average grain size o...

Lightweight advanced high strength steels (AHSS) with aluminum contents between 4 and 12 weight percent have been the subject of intense interest in the last decade because of an excellent combination of high strain rate toughness coupled with up to a 17% reduction in density. Fully austenitic cast steels with a nominal composition of Fe-30%Mn-9%Al-0.9%C are almost 15% less dense than quenched ...

This experimental study investigates the unclogging process of a propped fracture previously clogged, using synthetic dynamic load. Pressure oscillations inside are expected to flush out fine particles blocking flow. Laboratory experiments presented: fractures clogged with crushed natural sand; after applying load, significant increase intrinsic permeability is observed. The highest recovery ra...

Abstract In this study, the correlation between geometric properties of fracture network and stress variability in a fractured rock was studied. Initially, discrete networks were generated using stochastic approach, then, considering tensorial nature stress, field under various tectonic conditions determined finite-difference method. Ultimately, data analyzed tensor-based mathematical relations...

Abstract Low temperature joining is desirable for aluminum-ceramics because aluminum has a large coefficient of thermal expansion. In the present work, Al2O3 to Al was performed at room by two-step deposition method including Ni electroless and Cu electrodeposition. The strength increased, fracture mode changed from Ni/Al2O3 interface that in substrate using porous or etching dense surface. Thu...

AA7075 aluminum alloy is widely used for several high-technology applications its high mechanical strength to weight ratio but still the subject of studies seeking a further increase in properties. A commercial powder used, either as-received or after ball-milling. Dense samples are prepared one step by Spark Plasma Sintering, at 550 °C with holding time 15 min and uniaxial pressure 100 MPa. No...