Fabrication, Characterization and Implementation of Thermo Resistive TiCu(N,O) Thin Films in a Polymer Injection Mold

Area of Science:

• Materials Science
• Polymer Engineering
• Sensor Technology

Background:

• Injection molding processes require precise temperature control for optimal polymer part quality.
• Existing temperature sensors often lack the sensitivity or durability for direct melt contact.
• Thermoresistive thin films offer potential for in-situ temperature monitoring.

Purpose of the Study:

• To develop and characterize nitrogen- and oxygen-doped titanium-copper (TiCu(N,O)) thin films for temperature sensing.
• To optimize the thermoresistive signal response of these films for dynamic temperature control.
• To demonstrate the feasibility of using these novel thin films as sensor inserts in injection molds.

Main Methods:

• Fabrication of TiCu(N,O) thin films with varying nitrogen and oxygen doping levels.
• Characterization of the thermoresistive properties and temperature coefficient of resistance (TCR).
• Integration of optimized TiCu(N,O) films into a steel injection mold for a proof-of-concept experiment.

Main Results:

• Doping levels significantly influence the thermoresistive response of TiCu(N,O) films.
• Achieved TCR values of 2.29 × 10⁻² °C⁻¹, approximately six times higher than platinum sensors.
• Demonstrated sensitivity to temperature changes during the injection molding process in direct contact with polymer melt.

Conclusions:

• Developed TiCu(N,O) thin films are effective for dynamic temperature control in injection molding.
• The enhanced TCR and direct melt contact capability make them suitable for real-world applications.
• These novel sensor inserts represent an advancement in process monitoring for polymeric parts manufacturing.