Engineered Strain in 2D Materials by Direct Growth on Deterministically Patterned Grayscale Topographies

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Electrodeposition has been widely used to develop micro-mechanical devices because it offers high dimensional accuracy, flexibility, and relatively low cost. In devices such as mechanical watches, micro-components are required to be made from non-magnetic, hard, and wear-resistant materials. Copper is a common non-magnetic material used in the electrodeposition process, but its intrinsic low strength and soft mechanical behavior limit its use in such applications. These limitations can be overcome by devel

Under upper crustal conditions, rock pore space is often filled with fluids spanning various chemical compositions. The presence of fluids (water or others) was shown to affect the mechanical strength of porous rocks in both the brittle and ductile regimes. In the brittle regime, micromechanical models predict that porous rock strength is dictated by the frictional parameters and the fracture toughness of the material, while in the ductile regime, only by the fracture toughness of the material. Here, we inv

Titanium with porosity created by removal of spaceholders has reduced stiffness which can address longstanding orthopedic challenges of aseptic loosening and stress shielding. Here, we show that CaCl2 powder can have a dual use when integrated in titanium, (i) as a chemically inert pore-former (spaceholder) during laser powder-bed fusion (L-PBF) additive manufacturing and (ii) as a proposed osteogenic enhancer in the resulting Ti-CaCl2 composite. During L-PBF of powder blends, both Ti and CaCl2 are melted,

Accurately modeling the mechanical behavior of materials is crucial for numerous engineering applications. The quality of these models depends directly on the accuracy of the constitutive law that defines the stress–strain relation. However, discovering these constitutive material laws remains a significant challenge, in particular when only material deformation data is available. To address this challenge, unsupervised machine learning methods have been proposed to learn the constitutive law from deformati

Within the framework of the EuroFusion WPMAG project, an automatic laser-welding line was constructed to produce a 1 km long, empty stainless steel jacket demonstrator for the React & Wind (RW) conductor for EU-DEMO. Four 500 m long C-profiles made of 316L austenitic stainless steel were fabricated from ~8 m long sections using the manual TIG (Tungsten Inert Gas) welding method. A series of experimental investigations was carried out on the welded samples, including ferrite content measurements, microhardne

A three-dimensional frame-element based approach is presented to simulate cyclic inelastic interactions of local and lateral torsional buckling – collectively termed interactive buckling. The approach integrates a multiaxial fiber-based beam-column element termed the torsional fiber element, capable of representing deformation modes characteristic of inelastic warping and St Venant torsion with a multiaxial constitutive model that represents the effective constitutive response associated with cyclic inelast

Masonry walls are critical structural elements in buildings subjected to seismic actions. Their seismic performance is strongly influenced by the mechanical properties of the masonry units, particularly the vertical and horizontal compressive strengths of the bricks. During an earthquake, damage in unreinforced masonry (URM) walls initiates with cracking at the head and bed joints and can propagate through the bricks, affecting the overall drift capacity. Although current design recommendations recognize th

Amid profound transformations in the global energy landscape, the restructuring of electricity sectors has become a central element of national strategies to accelerate the growing integration of renewable energy sources (RES) into the power system. In parallel, the liberalization of the electricity industry in the 1990s has led to a significant transformation of this sector, rearranging the vertically integrated supply model into a market-regulated system. This has resulted in an increased need for flexibl

The majority of the seismic events in the Mediterranean region are hosted in carbonate-bearing rocks at depths representative of the semi-brittle regime. Within this regime, both brittle behavior (i.e. deformation is localized on the fractures and on the faults) and ductile one (i.e. deformation is distributed and accommodated in the rock core) coexist. The influence of this interplay on the nucleation and propagation of seismic events is poorly studied. Up to now, most experimental work has been conducted

One of the most alarming recent findings in geo-science is the dramatic rise in the rate of humaninduced earthquakes in the past decade. This is due to the fluid injection or extraction in deep reservoirs for hydrocarbon production, wastewater and CO2 storage and exploitation of geothermal resources which result in the reactivation of nearby faults. These reservoirs are often located 2-3 km depth (i.e. 30 MPa), and are hosted in or covered by sedimentary carbonate layers. As carbonate undergoes a brittle-du

Determination of the initial detaching volume is one of the major challenges in snow avalanche and debris flow forecast. Soil liquefaction due to loss of cohesion results in landslides, whereas quasi-brittle failure triggers the release of snow avalanches. Induced strain softening is the main cause of failure in both cases. In the recent decades, the finite element method has established as the preferred choice for stability analyses, thanks to the possibility of describing complex geometries, different mat

The tensile fatigue behaviour of ultra-high performance fibre reinforced concrete (UHPFRC) under constant amplitude fatigue cycles is presented. Three series of uniaxial tensile fatigue tests up to a maximum of 10 million cycles were conducted with the objective to determine the endurance limit of UHPFRC that was supposed to exist for this material. The fatigue tests reveal that an endurance limit exists in all three domains of UHPFRC tensile behaviour at S-ratios ranging from 0.70 to 0.45 with S being the

Engineering issues for which the understanding of the chemo-mechanical behaviour of soils is relevant include wellbore stability problems, the salinification of groundwater, and nuclear waste storage. However, despite the vast number of situations in which couplings between chemistry and mechanics occur, the available constitutive models rely on limited experimental evidence. This paper presents the results of an experimental programme on the chemo-mechanical behaviour of a non-swelling illite. The osmotic

A model based on the Euler-Bernoulli theory is used to assess the sensitivity of residual stresses in solid oxide fuel cells to the mechanical properties and geometry of the constituents. It considers different cell configurations, characterised by the presence or not of a compensating layer, and a cathode based on either lanthanum strontium manganite (LSM) or lanthanum strontium cobaltite ferrite (LSCF). The implementation of creep in the model provides insights into the parameters that affect the zero-str

The resistance as well as strain hardening and softening properties of UHPFRC depend on the type of matrix and mainly on the initial fibre dosage and final fibre distribution and orientation in the cast element. According to the final fibre distribution and orientation these properties may vary in a wide range. The strength and deformability distribution in a thin UHPFRC panel is studied. Tensile and flexural specimens cut in different directions and at different positions in the panel are analysed in order

Piezoresistive pressure sensors using classical deformable structures such as membranes progressively run into difficulties at very high pressures (above 1 to 2 kbar), due to the decreasing ratio between the available sensing strain on the outer membrane surface and the maximal materials strain experienced on the pressurised side. Therefore, a novel "isostatic" pressure sensor concept, whereby the sensing element is immersed in the pressure fluid, has been developed. This method in principle allows the meas

We present a method for modeling and animating a wide spectrum of volumetric objects, with material properties anywhere in the range from stiff elastic to highly plastic. Both the volume and the surface representation are point based, which allows arbitrarily large deviations form the original shape. In contrast to previous point based elasticity in computer graphics, our physical model is derived from continuum mechanics, which allows the specification of common material properties such as Young's Modulus

The importance of Fibre Reinforced Polymers (FRPs) as a material used for civil engineering purposes has grown in the last decade. Especially the introduction of pultrusion at an industrial level as a way to produce big batches of FRP made it possible to offer the advantages – like the high strength-to-weight ratio or the good corrosion resistance – at a reasonable cost. One issue when designing with pultruded FRPs are the connections. Up to now, connections between pultruded FRPs have been designed in the

Novel, highly sensitive piezoelectric acoustic sensors based on partially unclamped Pb(Zr-x, Ti1-x)O-3 (PZT) coated cantilever and bridge have been fabricated by silicon micromachining. High sensitivity at low frequencies (5-100 Hz) has been achieved by patterning very narrow slits (3 to 5 mum) around the structures. A typical response of 100 mV Pa-1 and a noise equivalent pressure of 1.6 mPa Hz(1/2) at 20 Hz have been measured using a 10 pF charge amplifier. Stress compensation, dry etching and integration

A process has been developed where multiple yarns of commingled glass and polypropylene are heated and placed to a desired geometry. The placed unidirectional (UD) tow is then encapsulated by over-moulding with glass mat thermoplastics (GMTs). The effects of both force (20 80 N), with an equivalent pressure range of 8 46 bar, and the displacement rate (20 100 mm/s) during tow placement on void content and flexural modulus were investigated for nine placement conditions. Placement rate affected the tow quali

Engineered Strain in 2D Materials by Direct Growth on Deterministically Patterned Grayscale Topographies

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Electrochemical deposition of composite materials: unravelling the process-structure-property nexus

Influence of fluid chemical composition on fracture toughness and frictional strength weakening: Sandstone brittle and ductile strength constraints

Laser powder-bed fusion of titanium with multifunctional CaCl2 spaceholders

Learning physics-consistent material behavior from dynamic displacements

Microstructure, mechanical properties and residual stress of welded stainless-steel jackets for React & Wind conductor in EU-DEMO

A torsional fiber element and a multiaxial softening model to simulate cyclic interactive buckling in wide-flanged steel members

Influence of the Horizontal-to-Vertical Compressive Strength Ratio of Hollow Clay Bricks on the In-Plane Lateral Loading Behaviour of Unreinforced Masonry Walls

Modeling, optimization and experimental assessment of transient-induced fatigue in hydraulic machines

On the stability of carbonate-bearing faults at the brittle-to-ductile transition

Frictional behaviour of carbonate bearing faults at brittle-ductile transition

Mixed strain-displacement finite elements for landslide and avalanche release prediction

Tensile fatigue behaviour of Ultra-High Performance Fibre Reinforced Concrete (UHPFRC)

An experimental and constitutive investigation on the chemo-mechanical behaviour of a clay

Sensitivity of Stresses and Failure Mechanisms in SOFCs to the Mechanical Properties and Geometry of the Constitutive Layers

STRENGTH AND DEFORMABILITY DISTRIBUTION IN UHPFRC PANELS

LTCC ultra high isostatic pressure sensors

Point based animation of elastic, plastic and melting objects

Adhesively bonded lap joints of pultruded GFRP shapes

Piezoelectric Pb(Zr-x,Ti1-x)O-3 thin film cantilever and bridge acoustic sensors for miniaturized photoacoustic gas detectors

Robotic tow placement for local reinforcement of glass mat thermoplastics (GMTs)