Diffusion Brazing Holding Time
The diffusion brazing holding time is the period during which the workpiece is held at a specific temperature to diffuse alloying elements and raise the melting line. Too short a time can lead to incomplete bonding, too long a time can lead to over-bonding or deformation.
Physical-Chemical Mechanism of Action
The diffusion brazing holding time refers to the period during which the workpiece is held at a set temperature. During this time, alloying elements from the filler metal diffuse into the base material and push the melting line upward. This process requires precise time control to ensure homogeneous bonding.
Metallurgical Relevance & Risks in Welding
A too short diffusion brazing holding time can result in alloying elements not fully diffusing into the base material. This can lead to incomplete bonding and potential cracks or weak points in the weld. On the other hand, a too long diffusion brazing holding time can lead to over-diffusion of the alloying element, causing deformation or a fine, glass-hard structure, which impairs the toughness of the weld.
Workshop Practice & Instructions for Action
The diffusion brazing holding time should be precisely adhered to. This requires accurate temperature control and careful time measurement. For most materials, the recommended diffusion brazing holding time is between 5 and 10 minutes, depending on the specific alloy and material. It is important to follow the manufacturer's instructions and adjust time and temperature as needed.