In brazing, why is a higher melting point alloy significant?

The significance of using a higher melting point alloy in brazing lies in its ability to create stronger joints. Higher melting point alloys typically have improved mechanical properties, such as better tensile strength and resistance to deformation under stress, making the joints they form more robust. This is particularly important in applications where the joint will be subjected to high temperatures or loads.

In brazing, the filler metal is melted above 450 °C (842 °F) and flows into the joint by capillary action. A higher melting point alloy ensures that the joint maintains its integrity under conditions that might compromise a lower melting point filler. Additionally, these alloys can often withstand harsher environments, such as increased thermal cycling or corrosive conditions, further enhancing the durability of the joint.

Using a lower melting point alloy might lead to a joint that is weaker and more susceptible to failure, especially in demanding applications. Therefore, the choice of a higher melting point alloy in brazing is crucial for achieving the desired strength and longevity of the joint.