Polydimethylsiloxane (PDMS) has cross-linked network structures and its properties have been regarded as dimensionally independent. Here we demonstrate that both the mechanical strength Young's modulus of PDMS membranes are thickness dependent transition from bulk behavior to dimension is predicted occur at a membrane about 200 µm. The thickness-dependent phenomenon attributed shear stress during fabrication, which proportional thickness-induced reorder polymer chain coils form stronger networks.

Carbon nanotubes (CNTs), including single-walled CNT (SWCNT) and multi-walled (MWCNT), have been regarded as the stiffest strongest materials ever developed are promising reinforcement fillers for developing nanocomposites. However, scientific community has puzzled about efficiency. Here we report CNT-reinforced nickel nanocomposites fabricated with an innovative electrochemical co-deposition process achieving good interfacial bonding between metallic matrices. Test results show that...

Copper (Cu) is widely used for electrical conduction but the inherent resistive heating not only wastes significant amounts of energy also creates severe reliability issues; therefore, how to increase copper's conductivity has been a goal with long history. Although nanometer-thin graphene regarded great potential conductive performance, published results are far from expectations and quest remains about actual enhancement efficiency graphene. Here, we demonstrated that single-layer in...

Metallic nanowires are promising as components in nanoscale systems including nanoelectronics. However, the application of made a single material is limited by properties used. We report here an effort to fabricate hybrid copper-coated carbon nanotube (CNT)—Cu/CNT nanowire, using microfluidic reactor. The fabrication copper/multi-walled (MWCNT) was realized electroless copper deposition technique which MWCNT templates and electrolyte were introduced separately into morphology structure...

Compact robust hydraulic actuators (pumps) are very important for space-related applications because of their capabilities in producing much larger forces per unit volume/mass than existing technologies. PZT stacks (pusher) have been widely identified developing compact (pump), but valves to match the inherent properties PZT, terms high frequency (up 100 kHz), load support MPa) and desired flow rate, missing. The authors developed novel solid nickel microvalve arrays using an situ UV-LIGA...

An experimental study of a capacitive micromachined ultrasonic transducer (CMUT) made from polymethyl methacrylate (PMMA)/graphene composite membrane is presented. Graphene has superior electrical and mechanical properties that make it desirable for sensing micro-electro-mechanical systems (MEMS) applications. The novel aspect this technique fabricates CMUTs the PMMA/graphene rather than more common silicon-based membrane. comprised bilayer graphene 320 nm PMMA layer. CMUT was formed by...

A microscale tribology test system has been developed at UCLA to measure friction and wear in MEMS components. Test results indicate that may not follow Amontons' law states the force is only related normal with a coefficient of friction. In this study, data constant it's influenced by crystal orientation, apparent contact area, material, fabrication process, as well applied. Explanation for discrepancy be adhesion, which critical issue microscale.

Based on solid-state plasma (SSP), an electromagnetically induced transparent (EIT) metamaterial is proposed. Simulations illustrate that the given has characteristics of adjustment, polarization insensitivity, and low dissipation. Because SSP can be coordinated in state I, ideal transmittance frequency band cover 8.0335–9.02531 GHz (a narrow band). If regulatory status switched to II, region will alter 9.7982–12.9275 broad As back forth between states I II under actual demand, tailored EIT...

The development and frequency response of a novel proof-of- concept prototype Mesoscale Actuator Device (MAD) is described in this paper. MAD similar to piezoelectric driven inchworm motors with the exception that mechanically interlocking microridges replace traditional frictional clamping mechanisms. interlocked microridges, microfabricated from single crystal silicon, are shown support macroscopic loads. Tests conducted on current design demonstrate 16 MPa shear or two sets 3 X 5 mm...

A novel proof-of-concept prototype Mesoscale Actuator Device (MAD) has been developed. The MAD is similar to piezoelectric driven inchworm motors with the exception that mechanically interlocking microridges replace traditional frictional clamping mechanisms. interlocked microridges, fabricated from single crystal silicon, increase load carrying capability of device substantially. Tests conducted on current design demonstrate support 16 MPa in shear or a 3/spl times/5 mm locked chip supports...

To address issues relating to large thermal resistance and low heat transfer efficiency between inside magnetocaloric materials (MCM) in all-solid-state room-temperature magnetic refrigeration technology, this study adopted the method of inserting high conductivity (HTCM) into MCM coupling Peltier elements MCMs enhance microcells, thereby improving performance system. In doing so, a two-dimensional simulation model was developed using COMSOL Multiphysics software. The cooling enhancement...

Abstract The shear strength of microridges fabricated using both anisotropic wet etching (KOH, TMAH and EDP) dry-etching methods (chlorine RIE) is presented in this paper. Shear strengths obtained a KOH concentration dependent, that the made with 45% solution has 65% larger than those by 30% KOH. EDP produce structures whose average are similar to solution. On other hand, dry chlorine RIE produces values 95% higher approaches containing crystal orientations. Strength variations attributed...

A robust microvalve has been designed, fabricated and tested for large flow rate hydraulic actuators. The objectives the actuator, same microvalve, are challenging MEMS based microvalves with (10 cc/sec), pressure support ability (up to 10 MPa) able operate at frequency kHz). designed meets all these requirements on simulation results micro reinforced valve flap a stopper. of is about 20 cc/sec under 50 psi no damages identified during repeating tests.