摘要:
A silicon carbide based composite material includes as a first component, a metal mainly consisting of aluminum or copper, and as a second component, particles mainly consisting of silicon carbide having high purity and few defects. The material is obtained by heating a compact of the raw material powder containing the first and second components at a temperature not lower than the melting point of the metal mainly consisting of aluminum or copper, and by forging and solidifying under pressure. Preferably, the silicon carbide raw material powder is prepared to have high purity by carrying out a preliminary treatment, or the material after forging or a material obtained through a conventional infiltration process is further heated at a temperature lower than the melting point of the first component. In this manner, an improved superior thermal conductivity can be obtained.
摘要:
A member for semiconductor devices comprising a composite alloy of aluminum or an aluminum alloy and silicon carbide, wherein silicon carbide grains are dispersed in aluminum or the aluminum alloy in an amount of from 10 to 70% by weight, the amount of nitrogen in the surface of the member is larger than that in the inside thereof, and the ratio of aluminum or the aluminum alloy to silicon carbide is the same in the surface and the inside. The member is produced by mixing powdery materials of aluminum or an aluminum alloy and silicon carbide, compacting the mixed powder, and sintering the compact in a non-oxidizing atmosphere containing nitrogen gas, at a temperature between 600.degree. C. and the melting point of aluminum. The member is lightweight and has high thermal conductivity as well as thermal expansion coefficient which is well matches with that of ceramics and others. Therefore, the member is especially favorable to high-power devices.
摘要:
A member for semiconductor devices comprising a composite alloy of aluminum or an aluminum alloy and silicon carbide, wherein silicon carbide grains are dispersed in aluminum or the aluminum alloy in an amount of from 10 to 70% by weight, the amount of nitrogen in the surface of the member is larger than that in the inside thereof, and the ratio of aluminum or the aluminum alloy to silicon carbide is the same in the surface and the inside. The member is produced by mixing powdery materials of aluminum or an aluminum alloy and silicon carbide, compacting the mixed powder, and sintering the compact in a non-oxidizing atmosphere containing nitrogen gas, at a temperature between 600° C. and the melting point of aluminum. The member is lightweight and has high thermal conductivity as well as thermal expansion coefficient which is well matches with that of ceramics and others. Therefore, the member is especially favorable to high-power devices.
摘要:
Disclosed herein is a photoreceptor for electrophotography having an over coating layer formed on a substrate and prepared by applying a composition containing silica particles, an organic compound chemically bonded thereto and a photo polymerization initiator and by curing said composition; said organic compound having an polymerizable unsaturated group, a group designated by Formula (1) or a group designated by Formula (2), and said silica particles and said organic compound being bonded with each other through a silyloxy group. The photoreceptor for electrophotography has not only excellent durabilities and an excellent resistance to printing but also excellent electrophoto characteristics such as sensitivity and a residual potential. ##STR1## (wherein --X-- is selected from --NH--, --O-- and --S--, --Y-- is an oxygen atom or a sulfur atom, and when --X-- is --O--, Y is said sulfur atom).
摘要:
In a powder forging process, a heated green compact is placed in a stationary die and subjected to a press-forging carried out mainly to reduce the thickness thereof by cooperation of the stationary die with a movable die. The press-forging is performed at two pressing steps. After placement of the green compact into the concave molding portion of the stationary die, the pressing step were carried out. Thus, it is possible to produce a forged product having a high strength and a high toughness. A heated heat insulator also may be placed in the stationary die to provide a temperature-retaining effect to the green compact before and during pressing.
摘要:
A method of producing rocket combustors wherein in forming an outer cylin by a powder metallurgical method on the outer side of a cylinder provided on its outer periphery with a cooling wall of channel construction having a plurality of grooves, a low-melting alloy is used as a filler to be filled into the grooves. It is also possible to form the outer cylinder after forming a Cu plating shell on the periphery of the inner cylinder filled with the low-melting alloy.
摘要:
A method of producing rocket combustors wherein in forming an outer cylin by a powder metallurgical method on the outer side of a cylinder provided on its outer periphery with a cooling wall of channel construction having a plurality of grooves (14), an Ni electroforming layer is formed on the outer side of the outer cylinder, and also a method of producing rocket combustors wherein an outer cylinder is of multilayer construction having two or more layers.
摘要:
A hydrogen storage material (1) having excellent hydrogen storage capability and having such a low hydrogen desorption temperature as not to significantly hinder the use thereof, and also capable of being mass-produced, and a manufacturing method of the same can be obtained. The hydrogen storage material has a layered deformation structure including plastic deformation, and one layer (2) of the layered deformation structure is formed from an alloy or compound including an element of groups 2A, 3A and 4A or an element of at least one of the groups 2A, 3A and 4A, and another layer (3) being in contact with the one layer is formed from an alloy or compound including an element of groups 6A, 7A and 8A or an element of at least one of the groups 6A, 7A and 8A.
摘要:
An injection molding method, an injection mold and a valve gate device, in which a movable pin moves easily, without excess force being exerted thereto, to properly open and close a gate. Closing a gate 10B by a cylindrical movable pin 27 allows excess resin to easily return back to a resin conveying path side through an outer edge portion at the end of the movable pin 27, so that even a large-diameter gate 10B can be reliably closed by the movable pin 27 which can be easily moved due to reduced resin resistance on the movable pin 27.
摘要:
A process for producing a heat-treated sintered iron alloy part, the process comprising: austenizing an iron-based sinter having a martensitic transformation initiation point (Ms point) of from 50.degree. to 350.degree. C., at a temperature not lower than the austenizing temperature (Ae1 point) of the sinter; quenching the austenized sinter at a cooling rate at which martensitic transformation occurs; and sizing or coining the quenched sinter at the time when the temperature of the sinter which is being quenched has reached the temperature range of from the Ms point to the Ae1 point.