Transient Liquid Phase Bonding
Diffusion welding with an interlayer is a joining process where a thinner interlayer with a lower melting point solidifies isothermally and enables joining at low temperature.
Physicochemical mechanism of action
The interlayer has a lower melting point than the metals being joined. During the welding process, it melts and forms a bridge between the two metals. The diffusion of atoms through this liquid interlayer allows the metals to join.
Metallurgical relevance & risks in welding
The correct selection of the interlayer is critical to ensure a homogeneous joint. A wrong choice can lead to incomplete or uneven joints, affecting strength and hardness. Additionally, the welding process must be isothermal to ensure a uniform joint.
Workshop practice & instructions
Choose an interlayer with a melting point below the highest melting point of the metals being joined. Ensure the process is isothermal to guarantee a homogeneous joint. Set the temperature so that the interlayer melts but the metals are not overheated.