摘要:
The present invention discloses a method of correcting the shape of a spray-formed article which has a concave bowing relative to the working surface of the article. Specifically, deviations of such articles from a desired predetermined shape are corrected by applying sufficient heat to a non-working surface to permanently remove at least a partial amount of the concave bowing while leaving the working surface substantially unmarred. This process is repeated iteratively until the article achieves the predetermined shape.
摘要:
One method of the present invention relates to a method for spray forming metal deposits. The method is comprised of providing a ceramic substrate having a spraying pattern for receiving sprayed metal particles, spraying metal particles onto the spraying pattern to form a metal deposit on the spraying pattern for at least a first spray period, controlling the spraying step during the first spray period so that the temperature of the deposited metal particles increases at an average rate of less than or equal to about 15° per minute. The first spray period can be defined as lasting until the temperature of the deposited metal particles is at or about a steady state temperature. The steady state temperature is preferably in the range of about 330° C. to about 370° C.
摘要:
According to one embodiment, a composite mold for use in molding a part having a textured surface is disclosed. The composite mold includes a mold base that forms the base of the composite mold. The mold base includes a mold base surface. The composite mold also includes a spray formed thin layer including a first surface having one or more fine features and a second surface opposing the first surface. The second surface is coupled to the mold base to form the composite mold having the first surface as the molding surface. The composite mold is capable of forming a molded part having a textured surface including surface features representing a reciprocal facsimile of the one or more fine features on the molding surface.
摘要:
One method of the present invention relates to a method for enhancing adhesion of spraying metal to a ceramic model. The method is comprised of providing the ceramic model having a spray surface, and modifying at least a portion of the spray surface if the ceramic model to enhance adhesion of spray metal to the spray surface.
摘要:
One method of the present invention includes introducing a slurry into a mold unit comprised of a mold contained within a casting receptacle and lowering the temperature of the slurry to freeze the slurry and form a freeze-cast substrate while controlling temperature gradients within the mold unit to minimize distortion in the freeze-cast substrate. Another method includes introducing a slurry into a mold unit comprised of a mold contained within a casting receptacle, placing insulation material around at least a portion of the casting receptacle to minimize distortion in the freeze-cast substrate by controlling temperature gradients within the mold unit, and lowering the temperature of the slurry to freeze the slurry to form a freeze-cast substrate.
摘要:
A method for implementing pre-heat treatment before spray forming begins to achieve stress control in the manufacture of a spray formed metallic article involves preheating either or both of a spray forming cell environment and a mold substrate, initiating application of the metallic spray forming material onto the mold substrate, and causing substantially homogenous initial metallic phase transformations from the austenite phase via a predetermined relationship between the initial application temperature of the spray-forming material and the initial temperature of either or both of the preheated cell environment and the preheated mold substrate.
摘要:
Atomized metal is deposited metal onto a substrate so as to cause at least partial solidification of the deposited metal; further atomized metal is deposited onto the partially solidified deposited metal on the substrate; and the metal deposited onto the partially solidified deposited metal is allowed to fully solidify on the substrate; the cooling of the further deposited metal, and the composition of the metal and/or of a gas used in the atomization of the further atomized metal being tailored such that volumetric contraction on solidification and cooling of the further deposited metal is compensated for, when the deposited metal has been cooled to ambient temperature, by volumetric expansion in a reaction or phase change in the further deposited metal.
摘要:
Metallic articles having heat transfer channels are produced by solidification of molten metallic material about pre-formed channel defining members such that a solidified metallic deposit having heat transfer channels is formed. The channel defining members may be in the form of either solid elements (which are subsequently removed to leave the channels), or conduit elements (which may remain permanently embedded in the article). Moulds, dies, cores and other tools for use in moulding or casting of plastics and metals are particularly suitably formed by the process, the heat transfer channels being used for cooling of the respective articles during use. The molten metallic material is preferably deposited by spray forming utilizing one or more sprays of molten metallic material.
摘要:
Method and apparatus for controlling stresses in a spray form process makes use of one dimensional modeling in which characteristics of a geometrical point are quantified by iterative detection, such as taking a surface temperature reading using a pyrometer. This temperature information is used in a one dimensional simulation to predict characteristics for a column from the point down through a spray-formed article to an interface with a substrate. The modeling technique can used with a plurality of geometrical points to model the whole article, and the one dimensional simulation can be integrated with robotic spray-forming controls to minimize residual stress in the spray-formed article.
摘要:
Method and apparatus for controlling a spray-forming process incorporating time, temperature, and transformation dependent stress relief techniques involves the manipulation of both temperature and time for strategic phase changes that result in a specific and planned volumetric increase. This manipulation is made based on controlling ongoing spray parameters to spray-form an article having a mixed-phase and interspersed makeup of metallic phases that minimizes residual stress in the article.