Boron based composites

Many barium aluminosilicate-based compositions will eventually react with the chromium oxide or aluminum oxide scales on the metal interconnect or metal edge rails to form barium chromate or a celsian phase at the interface [6], This can cause a mechanical weakness that is easily delaminated. Also, compositions that contain boron can react over time with water (steam) to produce B2(OH)2 or B(OH)3 gas. This can decompose the glass and greatly limit the lifetime of the seal. Thus many of the new investigations have emphasized low or no boron glass compositions. 

Dawe, ).R., and Cliff, M.D. (1998) Metal dinitramides novel oxidants for the preparation of boron based flare compositions. Proc.24th Ind.Pyrotech. Sem., Monterey, California, USA, July 27-31, 1998, pp. 789-810. 

Different methods used to prepare titanium diboride have been reviewed by Samsonov et al. (1975). At present, it is mainly produced as a powder by thermochemical reduction of boron and titanium oxides followed by hot pressing and sintering to process the final product. The less costly alternative appears to be to coat suitable substrate materials with TiB2 or TiB2-based composites by hot pressing, plasma spraying, chemical vapor deposition, etc. 

The principal theme of this section is concerned with the involvement of ESCA or XPS in various metal matrix-based composite systems. This section will be devoted to boron-, nitrogen-, aluminum-, and titanium-based composite systems and some of the ESCA results have been published elsewhere by the authors. 

In another paper [ the results of specific heat measurements on 10 metallic alloy samples were considered. This paper discusses specific heat measurements on four composite (i.e., fiber-reinforced) materials, one of which (boron/aluminum) is essentially metallic, and the other three are resin-based. The resin-based composites are more difficult to measure than metallic samples, and in analyzing the resulting data, the assembling of an appropriate fitting function is more complicated. As with the Fe-Ni base alloys [ ], specific heats were measured in the low-temperature range (3 to 20 K) and at the intermediate temperatures 80 K and 300 K. Because of difficulties associated with long thermal-relaxation times at these temperatures, considerable experimental scatter is associated with the results for the resin-based specimens. 

The specific heats of resin-based composites reinforced with glass, graphite, and boron are considered together. Curve-fitting trials were performed on the low-temperature data for S-glass/resin, and the results were applied to the analysis of the data for the other two composites. The intermediate-temperature results are presented as-measured. In the absence of any guidelines on the temperature dependence of the specific heat from 80 to 300 K, no attempt was made to adjust the data to the standard temperatures of 80.0 and 300.0 K. 

Boron Nitride-Based Composites In Combined Processes of Degradation of Dissolved Organics and Generation of Molecular Hydrogen... 

Table 7.13 shows results of assessment of rate of hydrogen generation from solutions of carboxylic acids (HCOOH, H2C2O4) using boron nitride-based composites in presence of Fenton system with addition of EDTA or fluorescein. 

Table 7.13 Results of photo catalytic degradation of H2C2O4 and HCOOH and hydrogen generation from their solutions in presence of boron nitride based composites (Cg y =0.1 M Ch 0 =3.75x 10" M Cj yg = 50mgi = 200mg v-joi = 20mi T 40°C).

Iron-containing boron nitride-based composites have good prospects in photocatalysis processes of deep degradation of dissolved organic matter (DOM) including processes with simultaneous hydrogen release. 

X. Sun, H. S. Lee, X. Q. Yang, J. McBreen, J. Electrochem. Soc. 1999, 146, 3655-3659. Comparative studies of the electrochemictil and thermal stahUity of two types of composite lithium battery electrolytes using boron-based anion receptors. 

B4C-TiB2 Boron carbide-based composites with TiB2 as the discontinuous reinforcing phase have been studied for cutting tools and wear parts by various authors [415, 427-433]. 

H. R. Frank and D. S. Phillip, Enhanced Boron Nitride Composition and Polymer Based High Thermal Conductivity Molding Compound, EP 0 794 227 B1 (2002). 

H. Ishida, Surface Treated Boron Nitride for Forming A Low Viscosity High Thermal Conductivity Polymer Based on Boron Nitride Composition and Method, US Patent, 6,160,042 (2000). 

Zinc borate is a boron-based fire retardant available as a fine powder with a chemical composition of (Zn0) < B203)y(H20)z. The most commonly used grades have the structure 2Zn0-3B203-zH20. 

This study has shown that the best composition of fillers promoting ceramization of silicone rubber-based composites consists of boron oxide (fluxing agent) and mica (refractory filler). Good mechanical properties and processability, in combination with very good mechanical properties and nanoporous structure after ceramization give to this composite large industrial implementation capacity. 

Kilinc Mert, Cakal Gaye O., Bayram Goknur, Eroglu Inci, and Ozkar Saim. Flame retardancy and mechanical properties of pet-based composites containing phosphorus and boron-based additives. J. Appl. Polym. Sci. 132 no. 22 (2015) 42016-42021. 

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