Methods for Fabricating Low Cost 3D Printed Parts With Expanded Material Properties

Technology

This invention describes a 3D printing system that includes a customized matrix having suitable material properties and geometric patterning to facilitate filling and retention of the filler material. The matrix is designed as a minimal structure to hold and constrain the casting material and define its 3D geometry. The matrix can be produced by 3D printing or by assembling premade geometric forms into a final matrix. Sensors can be incorporated into the premade geometric forms of the matrix to monitor various signals within the parts, such as stress, strain, pressure motion, temperature, etc. The filling is accomplished by injection of the casting material into the 3D construct. The casting material can be held in place by forces such as hydrophilic/hydrophobic/electrostatic interactions or through chemical interactions between the casting material and the 3D construct surface. The casting material can be further constrained by forces external to the 3D construct by filling the 3D construct with a filler material, and then subsequently submerging it in a desirable fluid. The submersion fluid can have specific properties to assist in the filling of the customized matrix by the filler material. Finally, the filler material retained within the customized matrix is cured or solidified to produce the object. The curing can occur in a gas, such as air or nitrogen, or in a submersion fluid. Since the various characteristics of the customized matrix, liquid filler material and submersion fluid can all be optimized together, a table/chart/algorithm can be created for optimal selection for object creation.

Problems Addressed

3D printing is a rapidly growing fabrication method to readily create structures across a range of applications. The process has the advantage of quickly generating parts that can be designed and fabricated, making it particularly suitable for prototyping. However, some limitations have restricted the use of 3D printing in larger scale manufacturing processes, or in material-demanding scenarios, such as biomedical applications. These limitations include cost of material, production time, and limited material selection. To address this issue, the inventors have developed a method to rapidly produce custom parts using a sequential process that overcomes material limitations of standard 3D printing.

Advantages

• Sequential process which overcomes material limitations of standard 3D printing
• Customized matrix with specific properties facilitates the retention of filler materials
• Customized matrix helps create objects comprising of cavities, holes, channels or voids