Mention one reason for the use of aluminum in thermite welding.
Thermite welding is a chemical welding process in which an exothermic reaction in which heat is produced, is used to supply the essential heat energy.
1)This reaction involves the burning of thermite, which is a mixture of fine aluminium powder and iron oxide in a ratio of about by weight.
2) Aluminium has a greater affinity for oxygen than iron. The reduction with aluminium is highly exothermic and generated the sufficient heat to melt the metal.
Thermite reaction:
That's why we use aluminium in thermite welding.