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Abrasive Jet Abrasive Jet Machining (AJM) is a non-traditional machining process that uses a high-speed stream of abrasive particles suspended in a gas (usually
Machining air or an inert gas) to remove material from a workpiece. AJM is often used for precision cutting, shaping, and finishing operations, particularly on
delicate or hard-to-machine materials.
In abrasive jet machining, the abrasive particles are accelerated to high velocities and directed towards the workpiece's surface. As the particles
impact the material, they erode and remove small fragments, gradually creating the desired shape or surface finish. The process can be controlled
to achieve varying degrees of material removal, and it is particularly suitable for intricate shapes and thin sections.
Key features and steps of the abrasive jet machining process include:
• Abrasive Particles: Abrasive particles are selected based on factors such as the workpiece material and the desired material removal rate.
Common abrasives include aluminium oxide, silicon carbide, and garnet.
• Nozzle Design: The abrasive particles are mixed with a carrier gas and directed through a specially designed nozzle. The nozzle shape and size
play a crucial role in controlling the jet's velocity and focus.
• Workpiece Setup: The workpiece is placed on a table, and the nozzle is positioned at the appropriate distance from the workpiece's surface.
• Abrasive Jet Generation: The carrier gas, carrying the abrasive particles, is pressurized and forced through the nozzle at high speeds. The
abrasive particles exit the nozzle in a focused stream and impact the workpiece.
• Material Removal: As the abrasive particles strike the workpiece, they cause micro-chipping and erosion of the material. The material is (Source of images:
gradually removed, and the process is repeated to achieve the desired shape or finish. http://www.myexamnotes.com/2014/09/
• Control and Monitoring: Parameters such as gas pressure, abrasive flow rate, nozzle-to-workpiece distance, and jet velocity are carefully abrasive-jet-machining-water-jet.html)
controlled to achieve the desired machining results.
Abrasive jet machining has several advantages:
• Capable of machining intricate shapes and fine details.
• Minimal heat generation, making it suitable for heat-sensitive materials.
• Does not create mechanical stresses or induce thermal damage.
• Can be used on a wide range of materials, including ceramics, glass, metals, and composites.
However, abrasive jet machining also has limitations:
• Lower material removal rates compared to some traditional machining methods.
• The process may not be as precise as other non-traditional methods like laser cutting.
• Finer abrasive particles can lead to better surface finishes but may reduce material removal rates.
Abrasive jet machining is used in various industries, including aerospace, electronics, jewellery making, and medical device manufacturing, where
precision cutting and delicate material removal are required.
Ultrasonic Ultrasonic Machining (USM) is a non-traditional machining process that utilizes the principle of ultrasonic vibrations to remove material from a
Machining workpiece. It is particularly effective for machining hard and brittle materials, such as ceramics, glass, and certain advanced alloys, where traditional
(USM) machining methods may be difficult or impractical.
In ultrasonic machining, the workpiece is typically held in a slurry or abrasive suspension that acts as a medium to transmit ultrasonic vibrations. A
tool, often made of softer material than the workpiece, is pressed against the workpiece surface while ultrasonic vibrations are applied. These
vibrations create a chipping or erosion effect, causing tiny abrasive particles suspended in the slurry to impact and remove material from the
workpiece.
Key features and steps of the ultrasonic machining process include:
• Tool and Workpiece Setup: The workpiece is submerged in a slurry containing abrasive particles. The tool, called a sonotrode or ultrasonic
horn, is positioned and held against the workpiece surface.

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