Influence of Molecular Structure of POM on Processability Within Metal Injection Molding

Area of Science:

• Materials Science
• Polymer Engineering
• Manufacturing Processes

Background:

• Metal Injection Molding (MIM) efficiently produces complex metal parts using polymer feedstocks.
• Polyoxymethylene (POM) is a common binder in MIM due to its rapid catalytic debinding.
• Thermal degradation of POM during processing can negatively impact feedstock characteristics and part quality.

Purpose of the Study:

• To investigate the impact of POM homopolymer (POM-H) and copolymer (POM-C) variations on MIM feedstock properties.
• To evaluate the thermal processing stability of different POM grades.
• To determine the influence of POM type and viscosity on green part properties and catalytic debinding.

Main Methods:

• Viscosity measurements were used to assess thermal degradation.
• Thermogravimetry analyzed the thermal stability of POM-H and POM-C.
• Feedstock characteristics, thermal processing stability, and green part properties were evaluated.

Main Results:

• POM-H showed more significant thermal degradation than POM-C, especially at higher temperatures.
• POM-C exhibited superior thermal stability compared to POM-H.
• Catalytic debinding performance was adequate across all tested POM materials.

Conclusions:

• POM-C grades are more thermally stable, making them preferable for MIM applications.
• Lower viscosity POM-C grades are recommended for optimizing feedstock processability in Metal Injection Molding.
• Understanding POM degradation is crucial for controlling MIM processability and final part quality.