摘要:
Referring to Figs. 2, 3 and 4, reference numeral (10) refers to a graphite electrode among three graphite electrodes that correspond to a three-phase AC power source. A graphite electrode is connected to each of the graphite electrodes (10) via a nipple. An electric current is supplied to these electrodes in an arc furnace of melt and refine metals. The invention deals with a method of refining and melting metals and a cooling apparatus used therefor, wherein, during the refining, a cooling liquid (11) which substantially consists of water is continuously sprayed onto the outer periphery (10a) of at least one graphite electrode (10) among the three graphite electrodes or, more particularly, onto the outer periphery (10a) of the graphite electrode (10) between an electrode holder and a furnace cover. In this case, the cooling liquid (11) is sprayed not in parallel with a horizontal level L-L, but upward or downward at an angle of 10° to 35° with respect to the level L-L to cool the electrode.
摘要:
A super heat-resistant silicon carbide fiber has an oxygen content of less than 1.0% by weight. In a process for producing the super heat-resistant silicon carbide fiber, a precursor fiber prepared by spinning a polycarbosilane having an oxygen content of less than 0.8% by weight is irradiated with a radiation in an oxygen-free atmosphere or in vacuo to make the precursor fiber infusible. The infusibilized fiber is fired in an oxygen-free atmosphere or in vacuo at a temperature of from 1000 to 2200°C without exposure to an oxidizing atmosphere; or stabilized in the same atmosphere at a temperature of from 300 to 600°C without exposure to an oxidizing atmosphere and fired in an oxygen-free atmosphere or in vacuo at a temperature of from 1000 to 2200°C.
摘要:
A silicon carbide fiber having a low specific electric resistance value and excellent mechanical properties including high tensile strength and tensile modulus comprises an amorphous carbon film which is formed on the surface thereof. In a method of manufacturing the same an antimelt-treated polycarbosilane fiber is heated at a temperature not exceeding 1000 o C in an atmosphere of inert gas and thereafter heated at a temperature of above 1000 o C and up to 1500 o C in an atmosphere of mixture of hydrocarbon gas and inert gas.
摘要:
A continuous inorganic fiber consisting of Si, N and 0 has excellent physical, chemical and electrically insulating properties, is superior to carbon fiber in wettability with metal, is low in reactivity with metal, and can be used not only as a reinforcing fiber for fiber-reinforcing type metals and fiber-reinforcing type ceramics, but also in electrical insulating materials and in heat-resistant materials.
摘要:
This invention provides a negative electrode active material for lithium ion capacitor, which reduces the thickness of a negative-electrode active material layer while maintaining the conventional level of energy density. The negative-electrode active material for a lithium ion capacitor is a composite carbon material manufactured by kneading a carbon black having an average particle diameter of 12 to 300 nm measured by the electron microscopy method with a carbon precursor such as pitch, the resulting mixture is baked or graphitized baking between 800°C to 3200°C, and then pulverized such that the average particle diameter (D 50 ) thereof is 1 to 20 µm and the BET specific surface area is between 100- 350 m 2 /g. An initial charging capacity is at least 700 mAh/g, and the cell volume is reduced as the thickness of the negative electrode active material layer becomes thinner than the conventional one.
摘要:
This invention provides a negative electrode active material for a lithium ion rechargeable battery, at low cost, which has a high electrode density, has excellent permeability to an electrolysis solution, has not significant loss in capacity by charging and discharging, and has good cycling properties. A binder is added to a negative electrode active material formed of a mixture of three graphite powders different from each other in hardness and shape, and the mixture is coated onto a metallic current collector, and the coated current collector is dried and pressed to prepare a negative electrode for a lithium ion rechargeable battery having an electrode density of not less than 1.7 g/cm3. The negative electrode active material comprises a graphite powder A (D = 0.04 to 0.06 P), a graphite powder B (D = 0.04 to 0.06 P), and a graphite powder C (D = 0.01 to 0.03 P), wherein P represents a press pressure, kN; and D represents an electrode density, g/cm3, the mixing weight ratio being A = 30 to 60%, B = 20 to 50%, and C = 5 to 30%. The negative electrode active material is advantageous in that voids which have been interconnected satisfactorily for permeation of the electrolysis solution into the electrode, can be ensured over the whole electrode, and the battery performance is not deteriorated even when expansion and shrinkage of particles are repeated upon storage and release of Li ions.