University of South Florida

Justin Troy Nussbaum

Nathan Brad Crane

Christopher Joseph Gardiner

Thomas McCrea Weller

Julie P Harmon

Eduardo Antonio Rojas

Garrett Michael Craft

Sintering methods comprising (a) providing a layer of powder material on a platform; (b) projecting incident light from a source onto a surface area of the layer of powder material, wherein the incident light is projected for a sufficient time to densify the layer of powder material and form a layer of densified material; (c) optionally cooling the layer of densified material to a sufficient temperature to solidify or vitrify the layer of densified material to form a layer of sintered material; and (d) repeating steps (a) to (c) to form a sintered article in a layer-wise fashion are disclosed. The incident light may cause complete melting of the powder material or heat the powder material above its glass transition temperature. In general, the incident light is projected simultaneously and for a time span substantially the same as formation of the layer of densified material.

System and method for improving mechanical properties of polymer powder bed fusion processes

A large area sintering platform, system, and methodology. The system includes a convection oven with a projection window disposed within a top surface of the oven. A platform is disposed within the oven below the window at a spaced distance away from the window. A powder is positioned on top of the platform, with a thermocouple positioned within the powder on the platform. A high intensity projector moves in sync with the platform, and uses low intensities and long exposure times to project an image through the window onto the powder and sinter the powder to fabricate the desired model layer by layer.

Large area sintering test platform and associated method of use

The disclosed subject matter relates to method for increasing the molecular weight of a polymer material during an additive manufacturing process. The method can comprise disposing a first layer of the polymer material at a target surface; exposing the first layer of the polymer material to an energy source for a sufficient period of time to sinter or melt and undergo a condensation reaction at least at a portion of the polymer material; controlling the condensation reaction to allow a desired increased number average molecular weight of the polymer material; and repeating the method steps to form an object in a layerwise fashion. Controlling the condensation reaction can comprise controlling and/or adjusting an energy 10 source-related parameter, a polymer-related parameter, a temperature related parameter, a vacuum related parameter, a process duration, a processing gas, an air flow volume and/or speed, or a combination thereof.

Layer-wise control of post condensation for additive manufacturing

A material processing and associated additive manufacturing system and method that utilizes high intensity light to fuse an entire layer of material, at one time, to create a three-dimensional component. The system and method of the present invention allows for each layer to be created in a fraction of the time, thereby reducing the overall time for a three-dimensional component to be created, thereby increasing control over the properties achieved.

Projection material processing system and associated method of use

The disclosed subject matter relates to methods for monitoring or controlling a manufacturing process of a material by determining when a variation in surface characteristics takes place. Such surface characteristics correlates to the processing condition of the material and can include density, roughness, porosity, or planarity on a surface of the material. The methods can include herein can include directing a solvent or energy on a surface of the material to form an at least partially modified surface, directing light at an incident angle with respect to the at least partially modified surface, measuring one or more predetermined properties of light reflected from the at least partially modified surface, determining that the material is fully processed based on the measured predetermined property of the light reflected, and optionally adjusting a processing parameter of the manufacturing process in response to the measured predetermined property.

Sintering monitoring method

In some embodiments, an apertured waveguide includes a wall comprising a plurality of apertures and an interior channel along which electromagnetic waves can propagate, the interior channel being defined at least in part by the wall.

Growing community of inventors

Tampa, FL, United States of America

Justin Troy Nussbaum