Short notes in detail on the following

1 USM

2 AJM

3 WJM

4 ECM1

5 CHM

6 EDM

7 PAM

8 LBM

9 EBM

1.USM-ULTRASONIC MACHINING

• It is a mechanical material removal process,used to erode material in the form of fine holes and cavities in hard or brittle workpieces.
• It uses formed tools,vibrations of high frequency and a suitable abrasive slurry-mix.

• The USM process is suitable for machining brittle materials such as

  • Glass
  • Ceramics
  • Semiconductors

for increasingly complex operations to provide intricate shapes and workpiece profiles

2.AJM-ABRASIVE JET MACHINING

• In AJM material removal occurs due to the impact of high velocity air/gas stream of abrasive particles on the workpiece.
• The abrasives are propelled by a high velocity gas to erode material from the workpiece.

3.WJM-WATER JET MACHINING

• Used in mining industry to cut hard rocks without any chemical effects.
• Used in aerospace industry.
• No heat is involved,so cut surface is cleaner.
• Almost any material can be cut.
• Environment friendly.
• Weldability of material is not reduced.

4.ECM-ELECTROCHEMICAL MACHINING PROCESS

• It is a non-conventional machining process.
• This process is widely used in many industries due to its advantages.
• This process is inverse of electroplating.
• ECM works on the basic principle of Faraday's law of electrolysis.

5.CHM-CHEMICAL MACHINING

• CHM is one chemical energy based NTM process.
• Here material is removed in ionic form due to controlled dissolution by chemical etchant.Etchant slowly dissolves metal to realize machining.
• It is independent of electrical conductivity of workpiece metal.So it can be applied for conductive and non-conductive materials.
• No additonal electrode is necessary as the chemical reaction takes place between etchant and workpiece.

6.EDM-ELECTRIC DISCHARGE MACHINING

• The EDM is an advanced machining process primarily used for machining materials which are difficult-to-machine with traditional techniques.
• However,only electrically conducting/semi-conducting materials can be machined by this process.
• The EDM process is best suited for making intricate cavities and contours.
• These would be difficult to produce with normal machines like grinders,end-mills or other cutting tools.
• The shape of the obtained cavity is a replica of the shape of the tool.

7.PAM-PLASMA ARC MACHINING

• It is used to remove material from workpiece.
• In this process a high velocity jet of high temperature gas is used to melt and remove material from the workpiece.This high velocity of hot gas is also known as plasma jet.
• When a gas or air is heated at a temperature of more than $5000^o C$,then it will start getting ionized into positive ions,negative ions and neutral ions.
• The gas or air is heated with arc and the plasma produced by heating gas is used to remove material from workpiece.

8.LBM-LASER BEAM MACHINING

• LASER is an abbreviation for Light Amplification by Stimulated Emission of Radiation.
• It is a device for producing a narrow beam of light,capable of travelling over vast distances without dispersion.
• A laser converts electrical energy into a highly coherent light beam.
• LBM is a form of machining,in which a laser is directed towards the work piece for machining.This process uses thermal energy to remove material from metallic or non-metallic surfaces.

9.EBM-ELCTRON BEAM MACHINING

• It is a non-traditional machining process in which no physical tool is used.
• Electron beam machining is same as Laser beam machining process in which except laser,high speed electron beam impinges on workpiece.
• This will generate high heat energy and melts and vaporize metal from work piece.
• This whole process takes place in vaccuum chamber.
• It is mostly used to drill holes in any shape.