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In order to increase the wettability between carbon fiber and aluminum matrix, pure nickel was applied as coating on carbon fiber. And scanning electron microscopy was used to characterize the microstructure of the coating, fiber and matrix. The tensile tests of carbon fiber and aluminum matrix were done to examine how the behavior of nickel layers with variation of applied pressure make an effect on the mechanical properties of composites. As the applied pressure increases, nickel layers were resolved into the aluminum matrix and ultimate tensile strength of the composite decreased. This was due to premature fracture of the reaction layer acting as a surface notch.

According to an irradiation damage model, the profile of an implanted ion at temperatures great enough for diffusion to occur will depend on the defect sink density in the material. To test this model, pure silicon wafers were prepared with high and low defect densities. These wafers were implanted with about 5 × 1019 As +2 m 2 at − 196, 300, and 600°C. After implanting the profiles were measured using Rutherford backscattering spectroscopy and secondary ion mass spectroscopy. The observed spreading of the As-profile contradicts initial theoretical predictions.

High temperature chlorine contaminated environments may be encountered in a number of modern industrial and energy conversion systems. Such environments have been shown to be extremely severe from a corrosion control standpoint. Rather little information is available on the corrosion properties of alloys in these environments, and the bulk of this information has been obtained in shortterm tests (24 hours or less). This paper will report the results of a series of high temperature corrosion tests performed on superalloys for periods up to 400 hours in an oxidizing environment consisting of argon containing 20 pet oxygen and 0.25 pct chlorine at 900 ° C.

Silicon is believed to be an almost perfectly brittle material with cleavage occurring on {111} planes. In such a material at room temperature cleavage is expected to occur prior to any dislocation nucleation. This behavior suggests that cleavage fracture may be used to produce usable flat surfaces. Attempts to show this have failed. Such fractures produced in semiconductor silicon tend to occur on planes of variable orientation resulting in surfaces with a poor surface finish. In order to learn more about the mechanisms involved in fracture of silicon we began a HREM study of hardness indent induced fractures in thin samples of oxidized silicon.Samples of single crystal silicon were oxidized in air for 100 hours at 1000°C. Two pieces of this material were glued together and 500 μm thick cross-section samples were cut from the combined piece. The cross-section samples were indented using a Vicker's microhardness tester to produce cracks. The cracks in the samples were preserved by thinning from the back side using a combination of mechanical grinding and ion milling.