摘要:
A method for spot-welding metallic materials includes: sandwiching the metallic materials with a pair of electrodes; a pre-heating step for pre-heating a region different from a given region which should be welded by applying electric power having a high frequency to the pair of electrodes; and a welding step for spot-welding a given region of the metallic materials by applying electric power for welding to the pair of electrodes. The heating time in the pre-heating step and that in the welding step are independently controlled.
摘要:
A welding structural part 1 is manufactured by overlapping the surfaces of steel sheets 2, and forming a weld zone by spot welding. The weld zone 3 includes: a weld nugget 4; and a heat affected zone 5 surrounding the weld nugget 4, wherein the hardness in the weld zone increases along an exterior region 6 of the heat affected zone 5 toward the heat affected zone 5, and then decreases along the heat affected zone 5 toward the central region of the weld nugget 4. In the boundary region between the weld nugget 4 and the heat affected zone 5, the weld nugget 4 may have a convex portion 4A bulging into the heat affected zone 5 along the overlapped portion. The steel sheets 2 contain carbon in 0.15 mass % or more.
摘要:
A welding equipment for metallic materials capable of performing heat treatment such as tempering based on partial heating in spot welding is provided. The welding equipment sandwiches metallic materials with a pair of electrodes, and heats different regions of the metallic materials by energization, with the pair of electrodes maintained at the same position with respect to the metallic materials. The welding equipment includes a first heating means connected to the pair of electrodes for heating and welding the internal region of the circle defined by projecting the cross-sectional area of the axis of the electrodes on the metallic materials by applying power having a low first frequency, a second heating means for heating a ring-shaped region along the circle by applying power having a second frequency that is higher than the first frequency, and an energization control unit for independently controlling the first and the second heating means.
摘要:
Raised contacts included within a semiconductor chip are bonded to respective external leads through the use of a bonding tool. The raised contacts and/or the external leads are varied in a fashion depending on their locations on a semiconductor substrate so as to compensate for lack of uniformity of the surface temperature of the bonding tool.
摘要:
Electrodes are formed on one major surface of a semiconductor chip and electrically connected to lead electrodes carried by a support substrate. A cover plate is fixed to the opposing major surface of the semiconductor chip to determine one major surface of semiconductor device. Remaining surfaces of the semiconductor chip are encapsulated by a resin mold. The cover plate comprises a flexible glass cloth impregnated with half cured epoxy resin.
摘要:
A high-strength die-quenched part 1 is formed by heating a high-strength steel sheet 11 up to an austenite region, hot stamping and cooling inside a mold, and its microstructure has the martensite wherein carbide particles 2 are finely dispersed over an entire region including prior-austenite grain boundaries. It is desirable that the prior-austenite grain size in the microstructure of the high-strength steel sheet, which is a base material, be 10 μm or smaller. The high-strength die-quenched part has high-strength and high-ductility thanks to its martensite.
摘要:
A welding structural part 1 is manufactured by overlapping the surfaces of steel sheets 2, and forming a weld zone by spot welding. The weld zone 3 includes: a weld nugget 4; and a heat affected zone 5 surrounding the weld nugget 4, wherein the hardness in the weld zone increases along an exterior region 6 of the heat affected zone 5 toward the heat affected zone 5, and then decreases along the heat affected zone 5 toward the central region of the weld nugget 4. In the boundary region between the weld nugget 4 and the heat affected zone 5, the weld nugget 4 may have a convex portion 4A bulging into the heat affected zone 5 along the overlapped portion. The steel sheets 2 contain carbon in 0.15 mass % or more.
摘要:
A method of manufacturing a semiconductor device with a bump-electrode of gold crystal is disclosed. The method includes providing a semiconductor substrate, an insulative layer, an electrode section, passivation layer on the edge portion of the electrode section, a multi-layer film, and a bump electrode of gold crystal. The method further includes heat treatment of the bump electrode to form an anticorrosive layer between the electrode section and the lower layer of the multi-layer film. Removing the unnecessary multi-layer film, the anticorrosive layer is used as a mask for etching to simplify the process of manufacturing the semiconductor device.
摘要:
A semiconductor device comprises an insulating substrate such as a film carrier having wiring patterns formed thereon, lead electrodes connected to the wiring patterns, and a semiconductor chip bonded to the lead electrodes. The surface of the lead electrodes, to which the semiconductor chip is bonded, is smooth as compared with that of the wiring patterns, thereby ensuring accurate operation of the semiconductor device.
摘要:
A plastic encapsulant for a semiconductor chip comprises an epoxy resin, an organosilicon compound, a hardener, a pigment, and an organic solvent. The epoxy resin is an epichlorohydrin-bisphenol A type epoxy resin, and the organosilicon compound is an organosilicon compound with a methoxy group, preferably, three methoxy groups. The hardener is a resol type phenol resin hardener. The organic solvent is a mixture of ketones, alcohols, and aromatic hydrocarbons.