Building Metal Parts Without Melting: Solid-State 3D Printing System

This patent describes a system for building or repairing metal parts by frictionally heating and stirring materials together without melting them, precisely controlling the material's internal structure as it's made.

What it covers

This system builds 3D structures, coats surfaces, or repairs objects by feeding a filler material, like metal powder or wire, through a spinning tool onto a workpiece. Unlike traditional 3D printing that melts material, this system uses friction and mechanical stirring from the tool's rotation and movement to heat and join the materials in a solid state (Claim 1). A control unit, monitoring unit, and sensors work together, using temperature feedback to adjust how the material is deposited layer by layer (Claim 1). This process creates a “tailored microstructure” where the internal grains of the material are made at least five times smaller than in the original filler or workpiece, making the final part stronger (Claim 1). For example, it could add a new, stronger metal layer to a worn engine part without damaging the original structure with high heat.

What it doesn't cover

• —Does not cover additive manufacturing processes that rely on melting and then solidifying the material, such as laser powder bed fusion or arc welding.
• —Does not cover systems that do not actively refine the microstructure of the deposited material to achieve at least a five-fold reduction in grain size (Claim 1).
• —Does not cover systems that lack temperature feedback controls to adjust processing parameters during layer-by-layer deposition (Claim 1).
• —Does not cover methods of joining materials without the use of a rotating and/or translating tool that provides friction, heating, or mechanical stirring (Claim 1).
• —Does not cover systems that only dispense filler material without also providing coordinated movement of the spindle, tool, or workpiece (Claim 1).

The clever bit

The clever bit is precisely controlling the material's internal structure, specifically refining its grains by at least five times, during the solid-state deposition process. This is achieved by combining friction-based heating and mechanical stirring with real-time temperature feedback, allowing for on-the-fly adjustments to create stronger, more durable parts without ever melting the metal.

Why it matters

Traditional metal manufacturing often involves melting, which can weaken materials or introduce defects. This solid-state approach avoids melting, allowing for stronger, more durable parts with refined internal structures. It enables the creation of gradient materials, where properties change smoothly, and the repair of existing components without extensive heat damage. This technology is important for industries needing high-performance metal components, especially for critical applications in aerospace or defense.

Real-world examples

• 1.Repairing worn aerospace components with new material layers
• 2.Adding specialized features to existing metal parts
• 3.Building custom metal prototypes with enhanced strength
• 4.Creating multi-material components with tailored properties
• 5.Manufacturing high-performance parts for defense applications