CRAFTING MEDIUM CONTAINING A WATER-BASED BINDER COMPOSITION FOR THREE-DIMENSIONAL PRINTING

• Main Authors: BARBATI, Alexander C, MOOSBERG, Mats
• Format: Patent
• Language: English
• Published: 24.06.2021
• Subjects: AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING; CASTING; MAKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; PERFORMING OPERATIONS; POWDER METALLURGY; SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS, SLAG, OR MIXTURESCONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDEDFOR; SHAPING OR JOINING OF PLASTICS; TRANSPORTING; WORKING CEMENT, CLAY, OR STONE; WORKING METALLIC POWDER; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL

This invention relates to a three-dimensional printing. This invention in particularly relates to a crafting medium containing water-based binder for three dimensional printing. The present invention also relates to a system for making three-dimensional object and a method thereof. The three-dimensional objects with a powder plus binder constitution for sintering there are several problems, the binder is difficult to remove because it needs to be dissolved or burned out after the object is finished. The binder can also be hazardous and needs toxic substances to dissolve. While removing the binder there is a risk for cracks and deformities in the resulting object. The crafting medium which is in the paste form includes 40 volume %-80 volume % metal/ceramic powder, 1 volume %-5 volume % gelling organic material, and 15 volume %-60 volume % water. Also additional corrosion inhibitors, sintering aiding or lubrication additives in the range of 0.1-2 volume % can be added. The water-binder in the crafting medium is removed after deposition of each layer. During the three-dimensional printing around 60-90% of the water is removed during layer-by-layer deposition. This leaves a porous structure that still has some binder to keep the object rigid, but binder contents is small enough and object is porous enough to allow for sintering without a separate debinding step in post processing.