Analysis of Ceramic Molded Products by Thermal Analysis

Significance of the Topic

Ceramic manufacturing relies on the efficient removal of organic binders to ensure product integrity, reduce energy consumption and minimize CO₂ emissions. Thermal analysis offers rapid insight into decomposition behavior, enabling optimized debinding conditions that prevent defects and enhance production throughput.

Objectives and Overview of the Study

This work evaluates the impact of gas atmosphere on binder removal from injection-molded alumina ceramics. Using combined thermogravimetric-differential thermal analysis, thermomechanical analysis, and evolved-gas FTIR, the study aims to determine optimal conditions for rapid, defect-free debinding.

Methodology and Instrumentation

Analyses were conducted on Shimadzu DTG-60, TMA-60, and DTG-FTIR systems under both air and nitrogen atmospheres. Key parameters:

• Heating rate: 10–20 °C/min
• Temperature range: 25–600 °C
• Sample weight: ~16 mg (DTG), sample length ~5 mm (TMA)
• FTIR resolution: 8 cm⁻¹, interval: 30 s, 10 accumulations

Main Results and Discussion

Thermogravimetric data showed a 14 % weight loss in both atmospheres, confirming full binder removal by 600 °C. In air, decomposition began at a lower temperature and exhibited a strong exothermic peak, indicating oxidative runaway. Under nitrogen, the process was milder with a small endothermic feature near 400 °C.

TMA curves revealed initial expansion up to 60 °C (air) and 80 °C (N₂), followed by multistage contraction. A rapid contraction at ~200 °C coincided with binder decomposition, and no further dimensional change occurred above 400 °C.

FTIR analysis identified decyl methacrylate evolution at ~690 s and tracked CO₂ release starting at 220 °C, peaking around 360 °C, and showing a secondary release near 440 °C.

Benefits and Practical Applications

The combined thermal and gas-analysis approach enables:

• Data-driven optimization of debinding schedules
• Reduction of cycle time and energy use
• Prevention of cracking and deformation in ceramic parts

Future Trends and Potential Applications

Emerging opportunities include integration of real-time thermal analysis with process control systems, application of multivariate data evaluation, and expansion to novel ceramic formulations and additive manufacturing processes.

Conclusion

The synergy of DTG-DTA, TMA and FTIR evolved-gas analysis provides a robust framework for optimizing debinding in ceramic production. This methodology delivers rapid, reliable insights that support reduced processing times, lower energy consumption and defect-free products.

References

1) Tomohiro Wada and Taiki Horino, Development of Atmospheric Gas Technology for Dewax and Sintering in Fine Ceramics Products, TAIYO NIPPON SANSO Technical Report No.29 (2010).