In conventional machining process, the material is removed by the direct contact between tool and workpiece. The energy is utilized to rotate either workpiece or tool, and the cutting tool should be harder than workpiece (35-50% more hardness). In non-conventional or advanced machining process, energy is utilized in its direct form (thermal, mechanical and electrical etc.) to remove the material. The workpiece properties such as hardness, shape, and size are no longer barrier in non-conventional machining.  

Traditional, also termed conventional, machining requires the presence of a tool that is

harder than the workpiece to be machined. This tool should be penetrated in the

workpiece to a certain depth. Moreover, a relative motion between the tool and

workpiece is responsible for forming or generating the required shape. Tools have a

specific number of cutting edges of a known geometry. The cutting action removes the

machining allowance in the form of chips, which are visible to the naked eye.

An unconventional machining process (or non-traditional machining process) is a special type of machining process in which there is no direct contact between the tool and the workpiece. In unconventional machining, a form of energy is used to remove unwanted material from a given workpiece.

Read more at:

http://www.newagepublishers.com/samplechapter/001566.pdf

http://www.synergy.ac.in/intranet/classnotes/MMP1%20.pdf

The descriptions mentioned above are correct. But some other machining methods like UAM (ultrasonic assisted machining), Rotary turning, Turn-milling, RUM (Rotary ultrasonic machining) are also classified into non-conventional machining. In these methods, the used energy is much lower than conventional one, particularly in UAM, whereas there is a direct contact between tool and workpiece. So, the limit of non-conventional machining is wider than that said by others.

I think in UAM there is no contact between tool and workpiece

In UAM, tool- workpiece contact is periodical. Please read the attached articles.

Article Experimental and Numerical Study of Ultrasonically-Assisted Drilling

Article Analysis of linear vibration in rotary turning of AISI 4140 steel

Maybe you want to consider also Electrical Discharge Machining (EDM) among 'non conventional' machining methods; cf. (e.g.): https://www.researchgate.net/post/Is_this_possible_to_machine_SiC_ceramic_with_EDM

Thank you Carlos for your Answer

Regards,Azzam

Thank you Mohammad for your answer.

Regards, Azzam

 Thank you Deepak  for your answer.

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Thank you Himanshu for  your answer.

Regards,Azzam

conventional machining process remove the metal at macroscopic level by applying the mechanical forces in direct contact between tool and workpiece and the material is remove in form of metal chips. where as unconventional machining process does not produce chips. it remove the material at microscopic level that is very less in quantity.

Thank you Ankita for you answer

Regards ,Azzam

Dear Azzam

For Non- conventional machining process there is no direct contact between tool and work piece so cutting shear force not applicable for material remove and heat effected zone can be created. In case of conventional machining process , there is direct contact between tool and work piece so cutting shear force applied for removed a material.

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Than you Tansy fir your answer

Regards, Azzam

Dear Azzam,

I would like to put brief and clear illustrations on conventional and non-conventional process.

Non-conventional machines, on the other hand, are those machines that operate automatically with the help of computers and there is no need for human intervention or operator. These are usually controlled by an automatic robot or computers. Examples of operations that uses non-conventional machines are car painting in car manufacturing plants, welding car units and in manufacturing processes where in there is extreme high and low temperature involved that humans cannot withstand.

The method of conventional machining demands that there must be direct contact between the tool and the work material. For instance, a fast rotating cutter made of iron is necessary to cut an aluminum bar. This method requires physical contact of the cutting tool and material that needs to be cut. The process of non-conventional machining, on the other hand, employs modern and latest technology in processing. This process involves no contact between the machine tools and material. Examples of non-conventional tools used are infrared beam, laser beam, electric arc, plasma cutting and electric beam. The differences between the two are as follow:

· Non-conventional method uses tools that are less noisy thus preventing noise pollution.

· In conventional machining processes, there is a risk of tool wearing since physical contact is required to perform the job. This is not true when it comes to non-conventional machining processes.

· Non-conventional process promoted longer tool life because no direct contact is made between the tool and the materials.

· Tools used in non-conventional processes are more accurate and with higher precision compared to conventional tools that create conventional parts.

· When it comes to costs, non-conventional tools are more expensive compared to conventional ones.

· It is easier to find spare parts for conventional machines but harder for non-conventional ones.

· Non-conventional tools require skilled operators who are experts in machining because it has a complicated set up while conventional tools are easier to set-up and operate without the assistance of professionals.

Hope you like it. It work out for you.

Ashish