摘要:
The present invention relates to a method of hot rolling copper or copper alloys such as copper wires and coppr plates. The present invention has succeeded in remarkably prolonging useful life of the tools used for hot rolling, and improving the surface quality of the rolled products by replacing the conventional methods of hot rolling copper using tools made of cemented carbide, die steel, high-speed steel, etc. by a method using tolls made essentially of Si.sub.3 N.sub.4. Si.sub.3 N.sub.4 tools used in the present invention contain at least one kind of sintering aid selected from the group consisting of Al.sub.2 O.sub.3, AlN, MgO, Y.sub.2 O.sub.3 and ZrO.sub.2, have a sintering density of 90% or more, Rockwell hardness of 88 or more and an average particle diameter of 2.mu. or less, and contain .beta.-type Si.sub.3 N.sub.4 as a main ingredient.
摘要翻译:本发明涉及一种热轧铜或铜合金如铜线和铜板的方法。 本发明成功地延长了用于热轧的工具的使用寿命,并且通过使用由硬质合金,模具钢,高速钢制成的工具代替热轧铜的常规方法来提高轧制品的表面质量 等等,通过使用基本上由Si 3 N 4制成的费用的方法。 本发明中使用的Si 3 N 4工具包含至少一种选自Al 2 O 3,AlN,MgO,Y 2 O 3和ZrO 2的烧结助剂,烧结密度为90%以上,洛氏硬度为88以上,平均粒径为 粒径为2μm以下,含有β型Si 3 N 4为主要成分。
摘要:
A novel method of hot rolling iron and iron alloy rods, using a hot rolling tool comprising .beta.-Si.sub.3 N.sub.4 and a sintering aid selected from the group consisting of Al.sub.2 O.sub.3, AlN, MgO, Y.sub.2 O.sub.3 and ZrO.sub.2, and having a sintered density of 90% or more, Rockwell hardness of 88 or more and a mean particle size of 2.mu. or less.
摘要翻译:一种热轧铁和铁合金棒的新方法,使用包含β-Si 3 N 4的热轧工具和选自Al 2 O 3,AlN,MgO,Y 2 O 3和ZrO 2的烧结助剂,烧结密度为90%或 此外,洛氏硬度为88以上,平均粒径为2μm以下。
摘要:
A method for manufacturing a fiber reinforced silicon carbide or silicon nitride ceramic sintered body having silicon carbide or silicon nitride ceramic whiskers dispersed therein, which method involves mixing together silicon carbide or silicon nitride ceramic powder, whisker formation agents made up of at least one material selected from metal Si or an inorganic compound containing Si, an organic containing Si, amorphous silicon ceramic powder or a mixture of SiO.sub.2 and carbon, or Si, sintering additives, and a whisker accelerating amount of a whisker formation accelerator selected from Fe, Ni, Co, Cr, V, Ti, Ta, W or Mo; molding the mixture into a predetermined shape; heat treating the molded body at a temperature of 1300.degree. C. to 1750.degree. C. to produce silicon carbide or silicon nitride whiskers in the molded body and thereafter densifying and sintering the molded body at sintering temperatures in a non-oxidizing atmosphere. The silicon carbide and silicon nitride ceramics produced by said method have excellent heat-resistance characteristics and excellent impact and corrosion resistance, thus making these ceramics eminently suitable for structural materials where these properties are required.
摘要:
An electrically-conductive sintered compact of silicon nitride which is machinable by electrical discharge machining and a process to produce the same. TiN and/or TiC powder is added to a powder of silicon nitride in an amount 15-40% by volume to act as a conductivity-supplying agent while 0.01-3.0% by volume MgO and/or Al.sub.2 O.sub.3 powder is added as a sintering assistant. The mixed powders are then preformed in a desired shape and sintered in a nonoxidizing environment at 1,600.degree. C.-2,000.degree. C. to obtain a compact of silicon-nitride machinable by electrical discharge machining due to its electrical conductivity being at least 1 S.multidot.cm.sup.-1.
摘要翻译:可通过放电加工机加工的氮化硅导电烧结体及其制造方法。 将TiN和/或TiC粉末加入15-40体积%的氮化硅粉末中,作为导电性供给剂,同时添加0.01-3.0体积%的MgO和/或Al 2 O 3粉末作为烧结助剂 。 然后将混合粉末预成形为所需形状,并在1600℃-2000℃的非氧化环境中烧结,得到可通过放电加工机加工的氮化硅致密体,因为其导电率至少为1Sxcm- 1。
摘要:
A catalyst for concentrating hydrogen isotopes for use in performing hydrogen isotopes exchange between gaseous hydrogen and liquid water, the catalyst comprising a support of porous polytetrafluoroethylene having a total specific surface area of 2 to 80 m.sup.2 /g as a result of mixing therewith 0.5 to 15% by weight of fluorocarbon or a porous styrene polymer or styrene/divinylbenzene copolymer having a specific surface area of at least 150 m.sup.2 /g, and deposited on the support particles of at least one element selected from Group VIII of the Periodic Table. A method for producing a support of porous polytetrafluoroethylene for such catalyst is also disclosed.
摘要:
Less dispersion and more homogenized ceramics are produced by sintering ceramic materials, in particular, containing silicon nitride or silicon carbide as a predominant component with other assistants or additives, machining the surface of the resulting sintered compact and then subjecting the sintered compact to a heat treatment for homogenizing in a non-oxidizing atmosphere such as nitrogen or argon gas at a temperature of from the mass-transfer temperature at which the mass-transfer takes place in the interior of the ceramics to blunt the fine point of a crack to the sintering temperature of the ceramics.
摘要:
A process and an apparatus for manufacturing a fine powder of metals or ceramics are proposed in which a mixed gas of volatile metal compound and/or evaporated metal and a reaction gas is reacted in a discharged state while heating by laser beam.
摘要:
The invention relates to an aqueous electrolytic cathode and/or anode in which an aqueous solution of alkaline metal hydroxide is used or an active nickel or nickel alloy electrode having greater stability and smaller overvoltage under the condition of high current density for use in electrolysis of aqueous solution of alkaline metal halide, and the method for producing the same. Electrode material consisting of nickel or nickel alloy or electrode material of multiple layers comprising said electrode material coated with nickel or nickel alloy powder is forcibly subjected to oxidization and reduction treatments in repetition under a selected treatment temperature and atmosphere so that the surface area is expanded by the production of surface openings, thereby enabling to obtain an electrode having the said high properties.
摘要:
A method for producing a tubular multi-layered porous barrier comprising the step of depositing fine powder onto at least one of the inner and outer surfaces of a sintered tubular porous support member in a layer of uniform thickness to form a fine powder layer and pressurizing said powder layer against said support member to form a porous barrier layer on the support member.
摘要:
A control unit controls the use of a flash memory in which a recording area is divided into a plurality of blocks. The control unit includes a SRAM for storing management information regarding history that blocks have been used for recording information, the management information being updated every time each block has been used, and a selecting controller for selecting, with reference to the management information stored in the SRAM, a block in which information is to be written from among the plurality of blocks in the recording area of the flash memory so that all the blocks of the flash memory are uniformly used, wherein the information is recorded in the block selected by the selecting means in the flash memory. A facsimile machine has the flash memory for temporally recording image data to be transmitted and/or received, and the above control unit for controlling the flash memory so that the image data is recorded in a block of the flash memory.