Metallurgical bonding is the result of chemical bonding that occurs between a substrate and coating areas that are in close contact or diffused evenly. This process can be augmented by heat treatments, mainly post-spraying dispersion.
This method entails the joining of dissimilar metal through metallurgical means. This is normally achieved with the aid of clad metal, which is similar to one of the metals in the bond. This type of bonding is free from oxide films, voids and any form of discontinuities.
Metallurgy is among the main domains of material science and engineering, which conducts studies of the chemical and physical behavior of inter-metallic compounds as well as their combinations, referred to as alloys. Thus, metallurgical bonding involves metal technology and the way science is applied to metal production for manufacturers and consumers.
Metallurgical bonding can be divided into two categories:
- Ferrous metallurgical bonding – This is also referred to as black metallurgical bonding. It involves the alloys and processes that are iron-based. Ferrous metal production accounts for about 95% of the metal production worldwide.
- Non-ferrous metallurgical bonding – Also known as colored metallurgy, involves alloys and processes based on varying metals.
The main goal in metallurgical bonding is to obtain the best balance between the two different materials that are bonded together. This can be done by properly balancing properties such as:
- Weight
- Cost
- Hardness
- Toughness
- Strength
- Performance in extreme temperatures
- Fatigue resistance
- Corrosion resistance
Heat treatments can further alter these properties.
In order to study macroscopic and microscopic metal properties, metallurgists utilize a technique called metallography. This makes the process of metallurgical bonding more successful, since detailed information on mechanical properties, processing history and overall composition of metals can be obtained.