1. Purpose of a Sintering Furnace
A sintering furnace is specialized equipment used to process powder-metal compacts (green compacts) to achieve:
- Desired physical and mechanical properties
- Target microstructure
Applications include:
- Drying paste on silicon wafers
- Removing organic binders in powders
- Completing aluminum back-contact and grid line sintering
Essentially, the furnace converts loose or pressed powder into solid, dense, and structurally sound metal or alloy parts.
2. Working Principle
Sintering involves heating powder compacts below their melting point so that particles bond together. To ensure high-quality sintering, the furnace must precisely control:
- Sintering Temperature – High enough to allow particle bonding, alloying, and reduction reactions.
- Protective Atmosphere – To prevent oxidation and ensure desired chemical reactions.
- Compact Conveyance – Uniform transport of green compacts through the furnace.
- Heating and Cooling Rates – Proper ramp-up and cooling prevent deformation or internal stresses.
Processes controlled during sintering:
- Debinding / Wax removal – Eliminate lubricants or forming agents.
- Reduction – Convert metal oxides to pure metals if needed.
- Alloying – Promote uniform diffusion of alloy elements.
- Microstructure transformation – Achieve desired grain structure and density.
Summary:
A sintering furnace is essentially a precision-controlled high-temperature system that transforms powdered materials into dense, mechanically strong, and chemically uniform parts while carefully managing temperature, atmosphere, and time.