Cold Isostatic Pressing to Improve the Mechanical Performance of Additively Manufactured Metallic Components

Area of Science:

• Materials Science and Engineering
• Additive Manufacturing
• Mechanical Engineering

Background:

• Additive manufacturing (AM) offers novel design possibilities for complex components.
• Binder jetting is an efficient AM technique for metallic parts, requiring post-processing like sintering.
• AISI 316L stainless steel is a common material for AM applications.

Purpose of the Study:

• To investigate the effect of cold isostatic pressing (CIP) as a post-processing treatment on additively manufactured AISI 316L stainless steel.
• To evaluate the impact of CIP on the mechanical properties, specifically yield load and maximum carrying capacity.
• To analyze the microstructure and porosity of the material in relation to its manufacturing orientation.

Main Methods:

• Additive manufacturing of AISI 316L stainless steel components using binder jetting.
• Post-processing treatment involving cold isostatic pressing (CIP) at 5000 bar and room temperature.
• Mechanical property assessment using the small punch test.
• Microstructural and porosity analysis.

Main Results:

• Cold isostatic pressing (CIP) significantly increased the yield load and maximum carrying capacity of the AM AISI 316L steel.
• The small punch test indicated enhanced mechanical performance after CIP treatment.
• Microstructure and porosity were found to be homogeneously distributed, showing isotropic behavior regardless of layer deposition orientation.

Conclusions:

• Cold isostatic pressing is an effective post-processing method to improve the mechanical performance of additively manufactured AISI 316L stainless steel.
• CIP treatment enhances the structural integrity and load-bearing capabilities of binder-jetted components.
• The study confirms the isotropic nature of the material's microstructure and porosity, irrespective of AM build orientation.