Debinding Furnaces heat treatment for binder removal by melting or thermal degradation

Carbolite Gero offers a variety of different debinding furnaces to suit your application needs. Debinding causes a polymer binder to thermally decompose. The use of binders ensures cohesion between the powder particles and allows the component to keep its shape. This process is often used before sintering of metal or ceramic parts.

Safety options for debinding furnaces

The debinding process produces volatiles that can prove to be harmful. Precautions should be taken to reduce any risks. Carbolite Gero debinding furnaces are available with a range of options to optimise the production process.

Afterburner

An afterburner (left) is used to oxidize volatiles from the removal process into NO_x, CO₂, and H₂O. This ensures all volatiles are transformed into safer molecules and released into the environment. It burns all volatiles, including those with a boiling point below 20°C, e.g. hydrogen, ammonia, and ethane. 
 

Condensate trap

A condensate trap (right) is used to condensate all compounds over 20 °C. All volatiles with the boiling point lower than 20 °C are let through.

 

Catalytic Converter

A catalytic converter (left) is a heated ceramic component that is doped with noble metals. The oxidiser contains a high surface area which supports the oxidation of organic components or gasses like CO and NO. In comparison to the afterburner, the catalytic converter runs at much lower temperature. The catalytic converter is compatible with models AAF 3 & 7 as well as AAF 18 & 32.
 

Heated gas outlet with a heating band

A heated gas outlet (right) is used to prevent condensates from forming in the outlet.

If required due to the process or recommended by the customer, the afterburner and condensate trap can be combined. As experts in high-temperature technology we have multiple solutions in our portfolio to guide you to the right debinding furnace and safety equipment. Please contact us for any enquiries on a suitable solution for your application needs.

Thermal Debinding

A thermally induced decomposition and evaporation of the binder occurs due to gas flow through the debinding furnace. The gas flow guides vapours to leave through surface-connected pores within the sample.

A poor temperature distribution and an inhomogeneous binder removal can lead to the formation of cracks and other defects within the sample. Hence, it is necessary to regulate and control the heating rate and speed of the removal.

Temperature for debinding ranges from:

• Low Temperature Removal: room temperature – 200°C - for solvent removal.
• High Temperature Removal: 200°C - 600°C - for volatiles with higher boiling point.
• Backbone Binder Removal: ≥ 600°C.

Employing a multi-step debinding process, where the sample is set to dwell at various boiling points, ensures the complete removal of compounds. Heating too quickly can lead to an increase in expansion rates, potentially damaging the sample and the afterburner. This, in turn, can hinder the conversion of organic compounds into NO_x, CO₂, and H₂O. It is important to avoid trapped gasses and an incomplete removal process, as these lead to defects and an undesirable microstructure.

Термогравиметрический Анализ (ТГА)

To track and optimise the progress of thermal degradation, thermogravimetric analysis (TGA) technique is recommended.

A decrease in reactant mass is often seen with an increase of the output product. This change can be recorded by monitoring the real-time mass loss during the thermal cycle.

TGA up to 5g: Thermal Analyzers for thermo-analytic processes - ELTRA
TGA up to 2kg: Ashing Furnace AAF-BAL with integral balance - Carbolite Gero

Debinding Furnaces - Часто задаваемые вопросы