摘要:
The method of preparing an adhesive layer on a substrate includes introducing a thermally reactive powder comprising aluminum and a second metal into a plasma torch, wherein the thermally reactive powder is substantially free of binder, additive and contaminant and does not contain a significant amount of intermetallic compound into a plasma torch. An exothermic reaction is initiated within the thermally reactive powders in the plasma torch and the exotherming powders impinge onto a substrate, such that the heat generated by the exothermic reaction is generated predominantly on the substrate.
摘要:
The present invention is a filtering flow guide for hydrothermal reaction vessels--such as crystal growth apparatus--which improves crystal production efficiency and crystal quality without significantly slowing down flow velocities or crystal growth times. One embodiment of the flow guide fits inside a conventional hydrothermal autoclave for crystal growth, and includes at least one central inlet conduit by which crystal nutrient solution flows from the autoclave's dissolving zone into its growth chamber. A plurality of funnels encircle the inlet conduit, the funnels contiguous with each other along their lateral edges and with the inlet conduit's intake opening at the funnels' innermost edges. Each funnel may be substantially shaped as a hollow, inverted triangular pyramid with a nadir instead of an apex, the nadir opening into a filter-containing outlet. The inlet conduit, plurality of funnels and outlet tubes guide the flow of crystal nutrient solution optimally through the autoclave's dissolving and growth chambers, producing an even flow rate and pattern, and reducing wasteful crystal deposition. The inlet conduit, the funnels, or both elements, may further include optional filters positioned to enhance convective solution flow with minimal flow impedance. The flow guide thereby also filters out contaminants, producing high-purity, high-perfection crystals.
摘要:
There are provided a continuous frictional extrusion process for continuously producing a deformed fine grain solid metal composition suitable for semi-solid forming. The process is featured by a large range of produce dimension and by precise control of the process parameter, such as total deformation, extrusion temperature and speed. The total deformation is controlled to be larger than a Mises effective strain of 2.3 to obtain a deformed fine grain structure with enough distortion energy stored, having a grain size less than 30 .mu.m and a subgrain size less than 2 .mu.m. A method combining the continuous extrusion process of preparing semi-solid raw material with semi-solid forming of shaped articles is also disclosed.
摘要:
An apparatus and method for the forming of a shaped article includes a means for plasticizing a feed material; a die chamber; a means for delivering a plasticized feed material from the plasticizing means and into the die chamber, the delivery means in flow communication with the plasticizing means and the die chamber; and means for applying a pressure to a material in the die chamber. In operation, a feed material is introduced into a plasticizing source; the plasticized feed material is delivered to a die chamber connectable in flow communication with the plasticizing source; and supplemental pressure is applied to the plasticized feed material within the die chamber.
摘要:
An apparatus for continuously extruding shaped articles includes a frictional extrusion source for extruding a feed material, a chamber for holding frictionally extruded material received from the extrusion source, a plurality of die chambers, each of the die chambers receiving extruded material from the holding chamber, a conduit for directing extruded material from the holding chamber to each die chamber for selectively filling each die chamber with extruded feed material and a monitor for filling of each die chamber of said plurality of die chambers with extruded feed material. The conduit is responsive to the monitor so that extruded material can be directed from a filled die to chamber to an empty die chamber for subsequent filling, thereby permitting continuous extrusion.
摘要:
A method for preparing glass-coated microwires is provided. A metal in a glass tube is superheated in a high frequency induction field, whereby the glass tube softens. A thin capillary tube is drawn from the softened glass and the glass tube fills with molten metal. The metal-filled capillary enters a cooling zone in the superheated state and the rate of cooling is controlled such that a microcrystalline or amorphous metal microstructure is obtained. The cooling zone includes a stream of cooling liquid through which the capillary passes. The microstructure of the microwire is controlled by choice of amorphisizers, cooling rate, nature of the cooling liquid, location of the cooling stream, dwell time in the cooling stream and degree of superheating and supercooling of the metal.
摘要:
The method of preparing metal-coated metals includes providing a metal powder and a disintegrator with a working chamber equipped with counter-rotating disks. At least one of said disks is made of a material softer than said metal powder. The metal powder is introduced into the working chamber and the disks of the disintegrator are counter-rotated so as to cause the metal powder to strike the disks, whereby the disk is eroded by the colliding metal particles and a coating of the eroded material is formed on the metal powder and the metal-coated metal particles are collected at the exit end of the disintegrator.
摘要:
There is provided a continuous casting and rolling process for continuously producing a deformed fine grain solid metal composition suitable for semi-solid forming. The process is characterized by high throughput, continuity, and precise control of the process parameters, such as solidification rate, rolling temperature and speed and total deformation. The solidification rate is preferred to be in a range of 10 to 150° C./s, and the total deformation is controlled to be larger than a Mises effective strain of 2.3 to obtain a deformed fine grain structure with enough distortion energy. A method combining the continuous casting and rolling process of preparing semi-solid raw material with semi-solid forming of shaped articles is also disclosed.
摘要:
A metal-coated particle is prepared by providing a disintegrator apparatus with a working chamber containing counter-rotating disks equipped with teeth design to accelerate particles towards one another, providing a first material and a second metal as powders, such that the first material is harder than the second metal and introducing the first material and second metal powders into the working chamber of the disintegrator apparatus, whereby the soft second metal collides with the hard material and is coated onto the surface of the hard first material. A metal-coated metal with an intermetallic interface is prepared by introducing a first material and a second metal as powders into a disintegrator working chamber containing counter-rotating disks and teeth designed to accelerate particles towards one another. The first material harder than the second metal and is capable of reacting with the second metal to form an intermetallic compound. The disks of the disintegrator are counter-rotted so as to cause the metal powders to collide with each other, whereby the hard metal powder is mechanically coated by second metal. The rate of rotation of the counter-rotating disks are further increased in a high velocity process whereby high local temperatures generated on impact cause a reaction to occur at the first material/second metal interface to form an intermetallic compound.
摘要:
The method for preparing metal powders with a narrow particle size distribution includes providing a disintegrator with a working chamber containing counter-rotating disks equipped with teeth designed to impart high tangential velocities to particles contacting the teeth, introducing a metal melt as a liquid stream with a composition substantially corresponding to the final metal powder composition into the working chamber of the disintegrator, counter-rotating the disks, whereby the liquid stream of metal entering the chamber is broken up into small beads, which leave the surface of the teeth with high velocities, and whereby subsequent contact of the beads with the teeth of the disks further break up the liquid beads until the bead solidifies by heat loss to the disks and collecting a fine metal powder of narrow particle size distribution at the exit end of the working chamber.