Tang Chunhe

Improvement in oxidation resistance of the nuclear graphite by reaction-coated SiC coating

Abstract Graphite shows superior nuclear and high-temperature performance, and is used in nuclear reactors with enormous quantities. The oxidation resistance of graphite is very poor. Therefore, the application of graphite is only limited to restricted environment. SiC presents excellent resistance to oxidation because of the growth of a protective glassy or partially crystallized Si0 2 layer at the surface of the material. It is reported in this paper that a uniform and dense SiC coating is formed by the reaction of graphite and molten silicon. Oxidation experiments show that, when samples were heated at 1000°C in static air for 8 h, 68 wt% of the graphite was burnt off, whereas for the coated graphite only 1.7 wt%, and 1.0 wt% at 1500°C in air for 2 h.

Properties of solar selective absorbing CrSiO cermets after high temperature treatment

Abstract The temperature stability of solar selective absorbing CrSiO cermets on Cu and Cr/Cu substrates was tested. The cermets were prepared by rf sputtering. Thermal annealing up to 900°C was done in air, Ar and vacuum for periods up to 30 days. Some crystal growth and stable optical properties were observed.

Microstructure and reflectance of sputtered Au/MgO films on Cu

Solar selective absorbing Au/MgO cermet-films were produced by RF sputtering onto Cu substrates. The influence of sputtering parameters on microstructure and spectral reflectance was investigated. With a film thickness of 0.15 μm values of α=0.91 and ϵ=0.048 were measured.

Properties Of Solar Selective Absorbing Cr-SiO-cermets After High Temperature Treatment

The temperature stability of solar selective absorbing Cr-SiO-cermets on Cu and Cr/Cu-subsotrates was tested. The cermets were prepared by rf sputtering. Thermal annealing up to 900C was done in air, Ar and vacuum for periods up to 28 days. Some crystal growth and stable optical properties were observed.

Metallization development for AIN/W cofired substrate at low temperature

In this paper, metallization properties of AlN/W cofired substrate sintered at 1650°C were studied. The adhesion strength between W and AlN ceramic was improved by some methods, which including addition of several kinds of oxides mixture or metallic particles into W thick film ink. When MgO-Al2O3-SiO2 was used, glass bonding increased the adhesion strength and when metallic particles were added, W conductor resistance decreased obviously.