The AJM is one of the unconventional machining process

1. ABRASIVE JET MACHINING
Presented by
NAME : S.ARUNKUMAR
DEPARTMENT : MECHANICAL ENGINEERING
COLLEGE : SUDHARASAN ENGG COLLEGE

2. INDEX
• Introduction to AJM
• Component of AJM
• Working Parameter of AJM
• Advantages
• Disadvantages
• Conclusion

3. INTRODUCTION OF AJM
Abrasive jet machining (AJM) is a process
in which the material is removed from the work piece
due to impingement of fine grain abrasive by a high
velocity gas stream.
The stream of abrasive mixed gas is directed
to the work piece by suitably designed nozzle.
This process differs from the conventional sand
blasting in that the abrasive used is finer and the
process parameters and cutting action is carefully
controlled.

4. BLOCK DIAGRAM

5. COMPONENT OF AJM
The following components are used in
Abrasive jet machine,
 Compressor
 Mixing Chamber
 Nozzle
 Regulator And valves

6. SCHAMATIC LEYOUT

7. WORKING OF AJM
Abrasive jet machining is a process in which
material removal takes place due to erosive action
of a stream of fine-grained abrasive particles
impacting at high velocity on the work surface.
Fine-grained abrasive particles mixed in
suitable portion with high pressure carrier gas,
usually air, are directed through a suitably designed
nozzle.
The nozzle used imparts high velocity to the
carrier gas and thereby to the jet of abrasive
particles at the nozzle exit. This is directed onto the
work surface to be machined

8. WORKING OF AJM
The erosion of a surface by solid particles
entrained in a fluid stream has received consideration
attention from many investigators in the past.
The theory of erosion phenomena in such
situation is not fully understood and adequate data of
its governing parameters are not available; some of
these parameters are interdependent and difficult to
control.
The first phase involves the determination from
fluid condition, of the number, direction and velocity
of abrasive particles striking the work surface.

9. WORKING OF AJM
The first phase is essentially a two-phase (solid-
gas suspension) flow problem and is beyond the
scope of present work. The discussion will, therefore,
be confined to mechanism of material removal or
erosion rate.
The erosion of materials by surface impact of
hard particles is a complex phenomenon, consisting
of several simultaneous and interacting, typically
involving mechanical, chemical and material
parameters as well as complex mechanism

10. WORKING PARAMETERS IN AJM
• Carrier gas.
• Types of abrasives.
• Size of abrasive grains.
• Velocity of abrasive jet.
• Mean number of abrasive particles per writ volume of
carrier gas.
• Work material.
• Stand of distance
• Nozzle design.
• Shape of cut.

11. FACTORS AFFECTING
PROCESS
 Material removal rate (MRR).
 Geometry of cut.
 Roughness of surface hardness.
 The rate of nozzle wear.

12. ADVANTAGES
 There is no mechanical contact between the tool and
work piece.
 It can cut hole of intricate shapes in hard and brittle
materials.
 Surface finish obtained is high.
 Depth of surface damage is low.
 Power consumption is low.
 Capital cost is low.
 Accuracy up to 0.05 mm can be obtained.

13. LIMITATION
 Metal removal rate is low.
 Nozzle wear is high.
 In machining soft metals, abrasive get embedded into
the metals as a result an additional cleaning operation
is required.
 Stray cutting and tapering are unavoidable, thus,
machining accuracy is poor.
 Process tends to pollute the environment, so, dust
collecting system is required.

14. APPLICATION
 For cleaning of the spark plug and casting.
 Removal of flash mid parting lines from the injection
moulded parts.
 It’s widest used is in cutting, drilling, deburring and
cleaning of hard and brittle materials.
 The process is also used to machine thin section and
intricate shapes in hard and brittle materials.
 Deburring and cleaning of Plastic, Teflon, Nylon
components is another application of this process.
 It is used in producing high quality surfaces
 Production of high quality surface.

15. CONCLUSION
Abrasive jet machining can be used for
polishing, debarring and other finishing operation
where the rate of material removal is important,
while in operation such as micro-drilling and cutting
it is the erosion depth which is more relevant