Iwata, Japan
Iwata, Japan

Time filter

Source Type

Patent
Dowa Metaltech Co. | Date: 2016-09-28

In a method for producing a heat radiating plate 20, the method containing the steps of: finish cold-rolling an annealed material to obtain a strip; causing the strip to wind in the shape of a coil to prepare a coil stock; unwinding the coil stock by means of an uncoiler 10 to obtain a strip 12; causing the strip 12 to pass through a gap between the rolls of a leveler 14 to correct the shape thereof; progressively feeding the corrected strip 12 to a progressive die 18 via a feeder 16 to progressively press-working the strip 12 to produce a heat radiating plate 20, the finish cold-rolling is carried out so that a ratio of the Vickers hardness HV after the finish cold-rolling to the Vickers hardness HV before the finish cold-rolling is not less than 1.2, and the corrected strip 12 is allowed to bend due to its own weight between the leveler 14 and the feeder 16 so that the minimum value of deflection (L1L0) is 0.5 to 2.0 m assuming that L0 is a distance between a roll at the last sending side of the leveler 14 and a roll at the first entrance side of the feeder 16 and that L1 is the length of the strip 12 between the roll at the last sending side of the leveler 14 and the roll at the first entrance side of the feeder 16.


Patent
Dowa Metaltech Co. and Yazaki Corporation | Date: 2015-04-23

A female terminal includes a box portion which is formed into a quadrangular prism-like shape so as for a tab of a male terminal to fit therein by bending a copper alloy plate which is obtained by being continuously and repeatedly bent before an age heat treatment is applied thereto, which has a proof stress of 700 MPa or larger and a width of 10 mm or larger and in which no crack is produced therein when bent 180 degrees about a bending axis which is at right angle to a rolling direction of the copper alloy plate. The box portion comprises notches which are formed in inner sides of bent portions produced by bending the copper alloy plate. A depth of the notch is set to be in the range from to of a thickness of the copper alloy plate.


Patent
Dowa Metaltech Co. and Tokuyama Corporation | Date: 2015-09-23

After a wet blasting treatment for jetting a slurry, which contains spherical alumina as abrasive grains in a liquid, to the surface of a ceramic substrate 10 of aluminum nitride sintered body so that the ceramic substrate 10 has a residual stress of not higher than -50 MPa and so that the surface of the ceramic substrate 10 to be bonded to the metal plate 14 has an arithmetic average roughness Ra of 0.15 to 0.30 m, a ten-point average roughness Rz of 0.7 to 1.1 m and a maximum height Ry of 0.9 to 1.7 m while causing the ceramic substrate to have a flexural strength of not higher than 500 MPa and causing the thickness of a residual stress layer 10a formed along the surface of the ceramic substrate 10 to be 25 m or less, the metal plate 14 of copper or a copper alloy is bonded to the ceramic substrate 10, which is obtained by the wet blasting treatment, via a brazing filler metal 12 to produce a metal/ceramic bonding substrate which has an excellent bonding strength of the ceramic substrate 10 to the metal plate 14 and which has an excellent heat cycle resistance.


Patent
Dowa Metaltech Co. | Date: 2016-10-12

A silver-plated product, wherein the preferred orientation plane of a surface layer of silver is {111} plane and wherein the ratio of the full-width at half maximum of an X-ray diffraction peak on {111} plane after heating the silver-plated product at 50 C for 168 hours to the full-width at half maximum of an X-ray diffraction peak on {111} plane before the heating of the silver-plated product is not less than 0.5, is produced by forming the surface layer on a base material by electroplating at a liquid temperature of 12 to 24 C and a current density of 3 to 8 A/dm^(2) in a silver plating solution which contains 80 to 110 g/L of silver, 70 to 160 g/L of potassium cyanide and 55 to 70 mg/L of selenium, so as to cause the product of the concentration of potassium cyanide and the current density to be 840 g A/L dm^(2) or less.


Patent
Dowa Metaltech Co. | Date: 2016-07-27

In a method for producing an electronic part mounting substrate wherein an electronic part 14 is mounted on one major surface (a surface to which the electronic part 14 is to be bonded) of the metal plate 10 of copper, or aluminum or the aluminum alloy (when a plating film 20 of copper is formed on the surface), the one major surface of the metal plate 10 (or the surface of the plating film 20 of copper) is surface-machined to be coarsened so as to have a surface roughness of not less than 0.4 m, and then, a silver paste is applied on the surface-machined major surface (or the surface-machined surface of the plating film 20 of copper) to arrange the electronic part 14 thereon to sinter silver in the silver paste to form a silver bonding layer 12 to bond the electronic part 14 to the one major surface of the metal plate 10 (or the surface of the plating film 20 of copper) with the silver bonding layer 12.


[Problem] Provides is a Cu-Fe-P-Mg-based copper alloy sheet material that is excellent in terms of electrical conductivity, strength, bending workability, and stress relaxation resistance in the case where load stress is applied in TD. [Means for Resolution] The copper alloy sheet material contains, in mass%, Fe: 0.05 to 2.50%, Mg: 0.03 to 1.00%, and P: 0.01 to 0.20%, and the contents of these elements satisfy the relation Mg - 1.18 (P - Fe/3.6) 0.03. The Mg solid-solution ratio determined by the amount of dissolved Mg (mass%) /the Mg content of the alloy (mass%) 100 is 50% or more. The density of an Fe-P-based compound having a particle size of 50 nm or more is 10.00 particles/10 m^(2) or less, and the density of an Mg-P-based compound having a particle size of 100 nm or more is 10.00 particles/10 m^(2) or less.


Patent
Dowa Metaltech Co. | Date: 2016-01-27

There is provided a silver-plated product which has good thermal resistance, bendability and wear resistance. In a silver-plated product wherein a surface layer of silver having a thickness of 10 m or less is formed on a base material of copper or a copper alloy, the full-width at half maximum of a rocking curve on a preferred orientation plane (preferably {200} or {111} plane) of the surface layer is caused to be 2 to 8 , preferably 3 to 7 , to improve the out-of-plane orientation of the surface layer to improve the thermal resistance, bendability and wear resistance of the silver-plated product.


Patent
Dowa Metaltech Co. | Date: 2015-08-05

In a silver-plated product wherein a surface layer of silver is formed on the surface of a base material or on the surface of an underlying layer formed on the base material, the surface layer of silver is formed by electroplating in a silver plating bath which contains 1 to 15 mg/L of selenium and wherein a mass ratio of silver to free cyanogen is in the range of from 0.9 to 1.8, and thereafter, an aging treatment is carried out to produce a silver-plated product wherein an area fraction in {200} orientation of the surface layer is 15 % or more.


Patent
Nippon Light Metal Co. and Dowa Metaltech Co. | Date: 2015-01-28

A metal circuit board and a metal base plate are bonded to a ceramic substrate to form a metal-ceramic bonded substrate, then the metal base plate is arranged on one surface of the radiator via a brazing material with the metal base plate overlapping with the one surface of the radiator, a jig having a concave R surface is arranged on another surface of the radiator with the jig butting against the another surface of the radiator, a jig having a convex R surface protruding toward the metal-ceramic bonded substrate is brought into contact with another surface of the metal circuit board, and the metal-ceramic bonded substrate and the radiator are heat-bonded while they are pressurized by the radiator side jig and the metal-ceramic bonded substrate side jig, wherein a curvature radius R (mm) of the convex R surface and the concave R surface is 6500 R surface pressure (N/mm^(2)) 2000 + 12000.


[Problem] To provide a copper alloy sheet material that has a very high strength of a 0.2% offset yield strength of 980 MPa or more, and is good in the conductivity, the stress relaxation resistance property and the press workability. [Solution] A copper alloy sheet material: having a chemical composition containing from 2.50 to 4.00% in total of Ni and Co, from 0.50 to 2.00% of Co, from 0.70 to 1.50% of Si, from 0 to 0.50% of Fe, from 0 to 0.10% of Mg, from 0 to 0.50% of Sn, from 0 to 0.15% of Zn, from 0 to 0.07% of B, from 0 to 0.10% of P, from 0 to 0.10% of REM (rare earth elements), from 0 to 0.01% in total of Cr, Zr, Hf, Nb and S, the balance of Cu, and unavoidable impurities, all in terms of percentage by mass; having a number density of coarse secondary phase particles having a particle diameter of 5 m or more of 10 per mm^(2) or less, and a number density of fine secondary phase particles having a particle diameter of from 5 to 10 nm of 1.0 10^(9) per mm^(2) or more; and having an Si concentration in the parent phase of 0.10% by mass or more.

Loading Dowa Metaltech Co. collaborators
Loading Dowa Metaltech Co. collaborators