摘要:
The present invention relates to methods for the formation of ceramic bodies. Methods of the invention involve processing ceramic-forming compositions to form an integrally self-supporting or stabilized structure, which may then be sintered to give the full-density ceramic product. Methods of the invention may also involve densification of the ceramic body. In one set of embodiments, the volume of the integrally self-supporting structure is reduced by at least 20%. The present invention may produce ceramic bodies having greater strength and durability, since the ceramic-forming compositions may be low in viscosity and may be homogeneously blended, decreasing the possibility for defects.
摘要:
The present invention relates to methods for the formation of ceramic bodies. Methods of the invention involve processing ceramic-forming compositions to form an integrally self-supporting or stabilized structure, which may then be sintered to give the full-density ceramic product. Methods of the invention may also involve densification of the ceramic body. In one set of embodiments, the volume of the integrally self-supporting structure is reduced by at least 20%. The present invention may produce ceramic bodies having greater strength and durability, since the ceramic-forming compositions may be low in viscosity and may be homogeneously blended, decreasing the possibility for defects.
摘要:
Methods of manufacturing an article use three-dimensional printing for a portion of the manufacturing. Three-dimensionally printing is conducted onto a powder bed which contains both organic-solvent-soluble, water-insoluble particles and water soluble, organic-solvent-insoluble particles. The water-soluble particles which may be selected for properties such as size and may include more than one substance. The organic-solvent-insoluble particles may further include at least one substantially insoluble substance such as a member of the calcium phosphate family. Printing may be done using an aqueous binder liquid. After removal of unbound powder, the preform may be exposed to the vapor of an organic solvent which causes the particles of organic-soluble-polymer to fuse to each other. This may further be followed by dissolving out the water-soluble particles, if such particles were present in the powder. Solvent vapor fusing together with the use of porogen particles may also be used in manufacturing methods other than 3DP. Rather than using organic solvent, heat responsive particles can be used, and can be filmed by elevated temperatures. Articles that may be produced by the described methods exhibit features such as a high porosity and an ability to undergo large deformations without breaking, and by at least partial springback from such deformation. The springback may be substantially instantaneous or may be time-dependent involving a time period of at least several seconds.
摘要:
The invention includes biostructures which may be characterized as having substantially all of the organic-solvent-soluble material in the form of a network of irregularly shaped perforated films. The biostructure may further include particles of a substantially-insoluble material, which may be a member of the calcium phosphate family. The biostructure may be osteoconductive. The biostructure may further contain an Active Pharmaceutical Ingredient or other bioactive substance. The API may be a substance which stimulates the production of bone morphogenetic protein, such as Lovastatin or related substances, thereby making the biostructure effectively osteoinductive. One or more of the polymers may have a resorption rate in the human body such as to control the release of the API. Methods of manufacture are also disclosed.
摘要:
A system for producing three dimensional components by bonding together successive layers of a porous material with droplets of a binder material. A binder printhead has an array of nozzles which controllably supply jets of binder material droplets to the layers of porous material. The printhead is scanned in a raster scan fashion over each layer of porous material along a first scan axis in one direction to provide first fast scanning paths of droplets. The printhead is then moved laterally of such one direction and is then moved along the fast-scan axis in the opposite direction to provide second fast scanning paths of droplets which are interlaced with the first scanning paths. The supply of the droplets to the porous material can be controlled so as to control the overlapping thereof to produce various desired surface and interior characteristics of the components.
摘要:
A method and apparatus for growing a crystalline or poly-crystalline body from a melt is described, wherein the melt is retained by capillary attachment to edge features of a mesa crucible. The boundary profile of the resulting melt surface results in an effect which induces a ribbon grown from the surface of the melt to grow as a flat body. Further, the size of the melt pool is substantially reduced by bringing these edges close to the ribbon, thereby reducing the materials cost and electric power cost associated with the process.
摘要:
Crystalline silicon PV modules typically use tinned flat copper wire to increase the conductivity of a bus bar metallization and to interconnect to adjacent cells. Such a flat bus wire may be patterned with shallow v-shaped grooves using metal forming techniques, such as rolling, stamping and drawing. The grooves are designed so that incident light is reflected up toward the glass superstrate of the module at an internal interface angle that is large enough (typically greater than about 40°) so that the light undergoes total internal reflection at the glass-air interface and is reflected onto the solar cell. A photocurrent resulting from the normal impingement of light on a proto-type of such a patterned bus bar is at least 70% of the photocurrent resulting from the direct impingement on active cell area of the same light source. A typical face angle of about 60° may provide TIR for at least 50% of the light that strikes the bus wire as omni-directional illumination. Substantially all of the light that strikes the cover external surface at any external interface angle less than about 30 degrees relative to the perpendicular to the cover surface can experience TIR. Improvement in module efficiency comes at very small incremental cost and adds no extra steps in cell or module fabrication. Typical face size is between 5 and 150 microns, with spacing between crests of about twice that range. Grooves can be lengthwise along the conductor, or at an angle, or angles. Rather than grooves, inclined faces can form pyramids, or other shapes. The surface may beneficially be specular.
摘要:
A droplet generator and ink jet printhead assembly employing the droplet generator are disclosed. The droplet generator can operate with a wide range of fluids over a wide range of conditions, is easily serviced, and can be easily integrated into a machine such as a Three Dimensional Printing machine. The assembly includes a nozzle having an orifice, a liquid reservoir or supply for containing a liquid to be emitted from the nozzle and a non-resonant elastically deformable fluid conduit for conveying the liquid from the liquid reservoir to the nozzle. A transducer is disposed in abutting relation with the fluid conduit a predetermined distance from the nozzle. The transducer is energized by a suitable electrical signal, such as a sinusoidal signal. The transducer causes compression of the conduit and provides a wave which propagates along the fluid conduit and fluid contained therein toward the nozzle and orifice. This wave acts to perturb the stream formed at the orifice and to initiate the break-up of the stream into droplets. The utilization of an elastically deformable non-resonant conduit between the transducer and the nozzle mechanically decouples the nozzle from the remainder of the printhead assembly and provides filtering of undesired frequencies which might otherwise be imparted to the fluid and the nozzle.
摘要:
A method and apparatus for growing a crystalline or poly-crystalline body from a melt is described, wherein the melt is retained by capillary attachment to edge features of a mesa crucible. The boundary profile of the resulting melt surface results in an effect which induces a ribbon grown from the surface of the melt to grow as a flat body. Further, the size of the melt pool is substantially reduced by bringing these edges close to the ribbon, thereby reducing the materials cost and electric power cost associated with the process.
摘要:
Processes for providing enhanced thermal properties of tooling, particularly metal and metal/ceramic molds, made by solid free form fabrication techniques, such as the three dimensional printing process, and the tooling made by these processes are disclosed. The methods of enhancing thermal properties include incorporating integral contour coolant channels into the mold, adding surface textures to the coolant channels, creating high thermal conductivity paths between the surfaces and the coolant channels, and creating low thermal inertia regions in the mold.