摘要:
According to the inventive method for producing a composite part (4), a support body (1) is produced from a powder with a ferrous alloy base using powder metallurgy. A magnet body (2) which is based on an alloy that is rich in rare earths is applied to the support body (1) and both are then sintered in a furnace (1), whereby a solid joint is formed between the support body (1) and the magnet body (2).
摘要:
A surface-mount device attach method for attaching solder ball-grid array or solder column-grid array surface-mount devices to a printed circuit board where the conventional solder mask structure is replaced with a layer of plated nickel to prevent printed circuit board warping caused by the mismatch in the coefficients of thermal expansion between the conventional solder mask and the printed circuit board. A native nickel-oxide layer that forms on the surface of the exposed portions of the plated nickel layer functions as a solder dam.
摘要:
The present invention provides a diamond sintered compact tool. Which is excellent in economy as well as cutting edge strength. A diamond sintered compact cutting tool comprising a diamond sintered compact sintered at an ultra-high pressure and high temperature and a WC—Co cemented carbide substrate directly bonded to the diamond sintered compact during a step of sintering and brazed to a tool base through the WC—Co cemented carbide substrate, in which a ratio of the thickness of the WC—Co cemented carbide substrate to the thickness of the diamond sintered compact layer satisfies the relation of: 0.8≦WC—Co cemented carbide substrate/diamond sintered compact layer≦3.0 and the diamond sintered compact layer has a thickness of 0.05 mm to 0.5 mm, preferably 0.05 mm to 0.45 mm, more preferably 0.12 mm to 0.36 mm.
摘要:
A cemented carbide insert of a first grade has at least one cutting point consisting of a cemented carbide of a second grade with different composition and/or grain size with an uneven transition zone between the first and second grade.
摘要:
High energy flux infrared heaters are used to treat an object having a surface section and a base section such that a desired characteristic of the surface section is physically, chemically, or phasically changed while the base section remains unchanged.
摘要:
A method for forming a composite vapor-deposited film one side of which suitable for vapor-deposition on a phosphor surface of a CRT, such as a color television picture tube, has high light reflectivity, and the other side of which has a property to absorb radiant heat, and a composite vapor-deposition material suitable for vacuum deposition are disclosed. The composite vapor-deposition material has a high vapor-pressure metal envelope and a low vapor-pressure metal in the core region of the envelope. Low vapor-pressure metal powder should preferably be dispersed and held by high vapor-pressure metal powder in the core region. Vacuum deposition using this composite vapor-deposition material yields a composite deposited film having a composition comprising almost 100% of the high vapor-pressure metal formed in the initial stage of evaporation, and a composition comprising 100% of the low vapor-pressure metal formed in the final stage of evaporation.
摘要:
A method of producing a ceramic matrix composite is provided, which production method reduces metal residual percentage within matrix with little energy consumption, without requiring special external heating means and special equipment while it is industrially simple and at a low price. It is a method of producing a ceramic matrix composite having the steps of filling mixed powder obtained by mixing metal powder and boron nitride powder into a predetermined container to form a green compact having a porous structure, and infiltrating the above described green compact with molten Al to form a composite material containing metal boride and having aluminum nitride as a matrix. The green compact is formed by compressing the mixed powder whose mixing ratio of metal powder to boron nitride powder is 1:1.8 to 1:2.2 (molar ratio) so that porosity of the green compact is 34 to 42%.
摘要:
A method and corresponding device for compacting a powder material into a homogenous article. The method includes the steps of, placing the powder material in a molding cavity connected to a gas source, blowing gas into the lower end of the molding cavity so that the particles in the powder material are suspended in a gas stream, sealing the upper end of the molding cavity by an upper pressing punch, connecting the lower end of the molding cavity to a vacuum source, sealing the connection to the vacuum source by moving a lower punch relative to the lower end portion of the molding cavity, and thereafter compacting the powder material with the help of the pressing punch. The apparatus for performing the method includes a molding cavity having sidewalls, an upper and lower punch moveable within the molding cavity an opining in communication with the molding cavity for blowing gas into, and sucking gas out of the cavity, wherein the lower punch is moveable between a first position in which an upper end surface of the punch is located below the opening, to a second position in which the opening is covered by a sidewall of the lower punch.
摘要:
A method of bonding a particle material to near theoretical density, includes placing a particle material in a die. In the first stage, a pulsed current of about 1 to 20,000 amps., is applied to the particle material for a predetermined time period, and substantially simultaneously therewith, a shear force of about 5-50 MPa is applied. In the second stage, an axial pressure of about less than 1 to 2,000 MPa is applied to the particle material for a predetermined time period, and substantially simultaneously therewith, a steady current of about 1 to 20,000 amps. is applied. The method can be used to bond metallic, ceramic, intermetallic and composite materials to near-net shape, directly from precursors or elemental particle material without the need for synthesizing the material. The method may also be applied to perform combustion synthesis of a reactive material, followed by consolidation or joining to near-net shaped articles or parts. The method may further be applied to repair a damaged or worn substrate or part, coat a particle onto a substrate, and grow single crystals of a particle material.
摘要:
This invention relates to a method of manufacturing an improved ferritic or martensitic alloy based on iron and chromium strengthened by a dispersion of oxides, commonly called an Oxide Dispersion Strengthened or ODS alloy, and, more particularly to a method of manufacturing a ferritic or martensitic ODS alloy with large grains based on iron and chromium which has a single phase ferritic or martensitic matrix having an isotropic microstructure and a grain size that is sufficient to guarantee mechanical strength compatible with a use of this alloy at high temperature and/or under neutron irradiation. According to the invention, the method comprises slow cooling of an austenite at a cooling rate less than or equal to the critical cooling rate for transformation of this austenite into ferrite.