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This study examines the effects of bond pads on the measurement of thermal conductivity for micromachined polycrystalline silicon using suspended test structures and a steady state resistance method. Bond pad heating can invalidate the assumption of constant temperature boundary conditions used for data analysis. Bond pad temperatures above the heat sink temperature arise from conduction out of the bridge test element and Joule heating in the bond pad. Simulations results determined correction factors for the electrical resistance offset, Joule heating effects in the beam, and Joule heating in the bond pads. Fillets at the base of the beam reduce the effect of bond pad heating until they become too large.

Nanostructures exhibit strong adhesion, which gives rise to friction even without normal loads. For technological applications, friction involves non-zero compressive loads. However, such frictional behavior of the 1D nanostructures remains unknown. Taking SiC-SiO(2) core-shell nanowire films (NWFs) as a prototype, this paper reports strong friction of the 1D nanostructures. The maximum static frictional force between an NWF and a macroscopic solid surface is 5-12 times that between two macroscopic solids; the frictional coefficient scales similarly.

A low-cost, low-waste manufacturing method for advanced thermoset composite parts could improve market penetration of composites compared to other engineering materials such as aluminum or steel. Such a method could combine some of the new trends in composites manufacturing such as resin infusion (eliminates need for prepreg), out-ofautoclave consolidation, and snap curing. The feasibility of a hybrid process with these characteristics has been demonstrated by uniting liquid composite molding, resin curing by electron beam irradiation, and high pressure consolidation with specialized elastomeric tooling. To demonstrate feasibility, a mold set was designed to make flat, square four-ply woven carbon fiber parts by (1) vacuum-infusing dry preforms with an electron beam-curable epoxy resin in minutes, (2) applying 690 kPa of uniform pressure and consolidating in seconds using an elastomer-faced specialized elastomeric tooling tool and simple hydraulic press, and (3) curing in seconds using a 3 MeV electron beam source. To better understand how various process parameters affect part performance, parameters are varied in a simple design of experiments, and flexural strength and stiffness, thickness distribution, fiber and void volume fractions, surface roughness, and crosssectional characteristics (via microscopy) are measured and compared.