How to 3D Print Metal Parts with Easy-to-Remove Supports

This patent describes a method for 3D printing complex metal objects with support structures that can be easily removed after the final part is made solid, by using a special non-stick layer in between.

What it covers

The patent details a method for 3D printing metal objects and their support structures layer by layer (Claim 1). The "build material" is a mix of metal powder and a "binder system" (Claim 1). Crucially, a special "interface of non-sinterable material" is printed between the object and its supports (Claim 1). After printing, a "debinding" step removes the binder, and then "sintering" heats the parts, making them solid and dense (Claim 1). Because of the non-sinterable interface, the support structure can be easily separated from the finished metal object, sometimes with a simple mechanical force (Claim 13). For example, printing a metal bracket with an overhang would require supports, and this method ensures those supports don't fuse to the bracket during the final hardening step.

What it doesn't cover

• —Does not cover 3D printing processes that do not involve a sintering step for densification of the final object.
• —Does not cover support removal methods where the support and object are made of the exact same sinterable material throughout.
• —Does not cover 3D printing of non-metallic objects, as the claims specify a "metallic three-dimensional object" (Claim 1).
• —Does not cover methods where the interface material itself sinters and bonds to the object or support.
• —Does not cover support structures that are dissolved or melted away without the use of a non-sinterable interface.

The clever bit

The novelty lies in strategically placing a "non-sinterable material" as an interface layer between the object and its support structure. This prevents the object and support from fusing together during the high-temperature "sintering" process, allowing for simple, damage-free separation afterwards.

Why it matters

Additive manufacturing, especially with metals, often requires support structures for complex shapes. Removing these supports from fully dense metal parts can be difficult and costly, sometimes damaging the finished object. This patent addresses that challenge by making support removal much easier and cleaner, which can reduce post-processing time and improve part quality. This is particularly important for industries adopting metal 3D printing for functional parts.

Real-world examples

• 1.Desktop Metal's Bound Metal Deposition (BMD) systems
• 2.Metal 3D printed tooling
• 3.Complex metal brackets with overhangs
• 4.Custom metal components for aerospace or medical devices