PART QUALITY MONITORING IN A STEREOLITHOGRAPHIC ADDITIVE MANUFACTURING SYSTEM

• Main Author: Batchelder, J. Samuel
• Format: Patent
• Language: English
• Published: 09.06.2022
• Subjects: ADDITIVE MANUFACTURING TECHNOLOGY; ADDITIVE MANUFACTURING, i.e. MANUFACTURING OFTHREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVEAGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING,STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING; INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIRCHEMICAL OR PHYSICAL PROPERTIES; MEASURING; PERFORMING OPERATIONS; PHYSICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDEDFOR; SHAPING OR JOINING OF PLASTICS; TESTING; TRANSPORTING; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL

A method for 3D printing a part in a layer-wise manner includes providing a pool of polymerizable liquid in a vessel over a build window and positioning a downward-facing build platform in the pool, thereby defining a build region above the build window. The method includes selectively curing a volume of polymerizable liquid in the build region by imparting electromagnetic radiation through the build window to form a printed layer of the part adhered to the build platform and scanning at least a portion of the build window with monochromatic, polarized light along a plane of incidence. The method includes measuring a change in intensity and polarity of the light to obtain information about the printed layer. The method includes raising the build platform to a height of a next layer to be printed and modifying the electromagnetic energy imparted into the next layer based upon the obtained information to print a next layer. The imparting, scanning, measuring, raising and modifying steps are repeated until the part is printed.