why is aluminum oxide used more frequently than silicon carbide as an abrasive?What r the different types of tool feed mechanism in USM process.
It may well be cheaper. Making silicon carbide is fairly energy intensive.
Aluminium Oxide Grinding Wheel
Aluminum oxide and silicon carbide are used to grind two completely different sets of materials. Steels and other ferrous alloys are best ground with an aluminum oxide wheel, and the majority of grinding tasks are grinding ferrous alloys. At home, tools are made of steel, and so home bench grinders come with Al2O3 wheels. The same with handheld angle grinders - most welding is done with ferrous alloys. For aluminum and carbides, a silicon carbide wheel will yield better results.
Aluminum oxide is tougher and therefore better suited to grinding steel, and a lot of grinding is done on steel. Silicon carbide is harder, but quite brittle, it tends to break into sharp shapes which is an advantage for nonferrous and nonmetallic workpieces, but the lack of toughness makes it specialized abrasive and therefore it is used less than aluminum oxide.
