Indirect Induction Sintering of Metal Parts Produced through Material Extrusion Additive Manufacturing

Area of Science:

• Materials Science
• Additive Manufacturing
• Mechanical Engineering

Background:

• Material extrusion additive manufacturing offers a cost-effective method for producing complex industrial parts using filaments with high metallic or ceramic content.
• Traditional post-processing involves separate debinding and sintering steps, often requiring transportation to conventional furnaces, which is time-consuming and complex.
• Achieving high part density is crucial for industrial applications, but current methods present significant processing challenges.

Purpose of the Study:

• To investigate the effectiveness of indirect induction heating for densifying Fused Filament Fabricated (FFF) parts made from stainless steel 316L filaments.
• To develop and propose a hybrid machine integrating FFF with in situ induction sintering.
• To streamline the production process of metal parts manufactured via material extrusion.

Main Methods:

• Utilized a commercially available filament highly filled with stainless steel 316L powder.
• Employed indirect induction heating for the sintering process of FFF-fabricated parts.
• Developed a hybrid machine integrating Fused Filament Fabrication (FFF) with a local indirect induction heater for in situ sintering.

Main Results:

• Achieved near-fully dense parts with densities up to 99.8%.
• Demonstrated significantly reduced soaking times compared to conventional sintering methods.
• Successfully integrated FFF with in situ indirect induction sintering in a hybrid machine.

Conclusions:

• Indirect induction heating is an effective method for densifying stainless steel 316L FFF parts.
• The proposed hybrid machine simplifies metal part processing by enabling in situ sintering.
• This integrated approach significantly improves efficiency and reduces post-processing time in additive manufacturing.