Arvind Agarwal

Abstract

Currently, achieving an accurate measurement of the mechanical properties of ultra-soft materials requires specialized techniques, such as nano-indentation, atomic force microscope (AFM)-based techniques, or rheology. These highly specialized techniques provide only narrow and localized nanoscale characterization of ultra-soft samples. These techniques require sophisticated equipment and/or cannot perform measurements in ultra-soft heterogeneous systems. It is difficult to understand the meso/macro scale length structural behavior of a sample with limited insight into its local nanoscale characteristics. Some ultra-soft materials may exhibit a wide range of mechanical characteristics throughout different locations of the sample due to their anisotropic and heterogeneous nature. To overcome these drawbacks, there is a need for an easier, accurate, and accessible ultra-soft material testing platform. Ultra-soft materials cannot be mechanically characterized through existing macroscale indenters, which are conventionally made of metal and will typically pierce through the ultra-soft material sample due to indentation from high loads. As a result, such metal indenters fail to capture the adhesion forces, which are critical for ultra-soft material characterization. This piercing phenomenon leads to a grossly inaccurate estimation of the true mechanical properties of the ultra-soft sample.The FIU technology provides advantageous systems and methods for accurate characterization of the mechanical properties of ultra-soft materials through the use of a millimeter-scale (e.g., 10 millimeter (mm)-diameter), ultra-high molecular weight indenter probe. The indenter probe accurately captures the adhesion forces present during the approach and detachment segments of the indentation process.

Benefit

· Allows to measure the bulk mechanical properties of centimeter-scale ultra-soft materials through the indentation technique. · Allows for mechanical property testing of ultra-soft materials · Adaptable for conventional table-top mechanical frames. · Ease of accessibility and low cost of implementation

Market Application

Implant materials and technologies, Soft robotics, Tissue engineering technologies, Organ-on-chip technologies, Flexible Surgical equipment, Flexible electronics, Sensors and actuators, Structural and packaging materials, Foams and adhesives, Detergents, Cosmetics, Paints, Food additives, Lubricants and fuel additives

Abstract

Current benchmark magnesium alloys, such as the Mg-Al family, are thermally unstable at temperatures over 125 °C. The currently available alternative for elevated temperature applications is Mg-AE42, which can be used for temperatures up to 170 °C, above which there is an abrupt degradation of creep resistance. The price range for Mg-AE42 is extremely high. This invention uses an Mg-Sn alloy system, which can be used for elevated temperature applications higher than the currently available Mg-AE42 without compromising the mechanical strength at an affordable price. The novel alloy family can be made from available natural resources within the United States while offering improved mechanical properties and corrosion and creep resistance at half the cost of commercially available alloys.

Benefit

Better fuel economy with usage in car engine partsReduction in carbon dioxide emissions and environmental damage from vehiclesWithstand temperatures higher than commercially used alloysHalf the price of the raw materials per unit of the cheapest commercially available counterpartsWeight reduction in car engine parts will result in saving billions of dollars in the US

Market Application

Automotive industry for weight reduction to reduce emissionsBiomedical implantsAlternative for metals and polymers where enhanced mechanical properties are advantageous

Abstract

Graphene is a single layer of carbon atoms bound together in a honeycomb pattern which makes it a great conductor of electrons at room temperature. 3D Graphene foam (think of a porous sponge) is an ideal filler for ceramic composites (ceramic fibers embedded in a ceramic matrix) as the graphene-ceramic composites have improved strength, toughness, stiffness, and thermal-electrical conductivity. However, there are many practical challenges in its real-world application as graphene flakes tend to form clusters which can reduce its mechanical strength and toughness. The non-homogeneous distribution can also impede the electrical and thermal properties of the composites. Though there are various physical and chemical methods to achieve homogeneity, the techniques are expensive, time-consuming and the addition of secondary chemical particles can damage graphene flakesTo improve the microstructure homogeneity, macro-porous graphene foam (GrF) is a promising material for developing composites because of its ultra-low density, high surface area, and large pore size. The structure of GrF can be exploited by infiltration with polymer resin followed by curing to create a composite material with a homogeneous distribution of the filler phase. FIU scientists have invented a method to produce Graphene foam ceramic composite where the GrF is surrounded by and infiltrated with a Low-Temperature Co-fired Ceramic (LTCC) matrix. This material shows outstanding flexibility, resistance to failure, high density, damping capability, and electrical and thermal conductivity.

Benefit

Superior ceramic composites with the additional advantages of enhanced electrical and thermal properties.Structural material with enhanced failure resistance, toughness, and flexibility

Market Application

The GrF-reinforced LTCC has applications for strain sensors, Li-ion batteries, supercapacitors, electrochemical biosensors, biocompatible scaffold, consumer electronics, electromagnetic shields, fuel cells, thermal interfaces, acoustic backers, vibration dampeners, and metallic materials with ultra-high stiffness and fatigue resistance.GrF-ceramic composites can also be part of medical implants and ceramic packaging material.