1. Abrasive jet machining (AJM)
Abrasive jet machining is a metal removing process, in this process metal is
removed with the help of high velocity steam of abrasive particle on it. In AJM metal is
removing with the help of erosion. The high velocity (about 200-400 m/s) of dry air,
nitrogen or carbon dioxide with abrasive particle is focused on workpiece under
controlled condition. The rate of metal removing is depending on the flow rate and the
size of abrasive particle, commonly used abrasive on AJM is Sic, Sodium bicarbonate
glass beds.
Abrasive particle and high pressure air is supplied to the mixing chamber at pressure of
2 to 8 kgf/cm2 and the chamber is vibrating for mixing of abrasive with gas.
2.
3. Element of AJM
a. Nozzle: Nozzle is usually made from the tungsten carbide or sapphire.
b. Abrasive: Commonly use abrasive are Sic, sodium bicarbonate, dolomite and glass beads.
c. Mixing chamber:
d. Vibrating device:
e. Mixing chamber:
4. Advantage of AJM
a) Low capital cost.
b) No heat is generating.
c) Fragile, brittle or heat sensitive material can be easily machined
without damage.
5. Disadvantage:
a) Accuracy is poor.
b) Slow metal removal rate.
c) Can’t use for machining ductile material.
d) Abrasive particle are not reusable.
6. Application:
a) Remove plating, anodic, or thermal oxide coating.
b) For abrading and frosting of glass.
c) Machining semiconductor such as germanium,gallum etc.
