I think is possible to study the edge of cut measuring the cutting forces. Similar edge shapes with differents coatings, can produce differents cutting forces. Normally, when the cutting force at equal cutting conditions, gives smaller forces, the cutting tool is better, and the edge takes longer.

in case of ductile material study and investigate chip formation. For good surface finish and machining process, a continuous chips are formed. Also, here w/p diameter also plays a vital role. Other than FE and experimental, investigating the formation of chip for different tool and then correlating with machining parameters can also look upon. 

The idea from Agari, is very important. If you want you can collect chip during differents experimental test and clasified the shape with the ISO 3685 standard. Always chip "speaks" about the process.

It depends on what you would like to investigate on. I provide some examples here for you:

For prediction of temperature on tool, FDM method is quite a good way to go. Look at the following papers:

http://www.sciencedirect.com/science/article/pii/S0890695502000391

http://www.sciencedirect.com/science/article/pii/S0890695504001300

For stress distribution on the tool there is no other method than FEM to do so. But for stress distribution on shear zones, I would suggest Slip-line technique. But you should be really careful for application of this method on different material because of its assumptions. Look at:

 http://www.sciencedirect.com/science/article/pii/S0924013610003080

For tool wear prediction, there are some mechanistic and semi analytical models:

http://www.sciencedirect.com/science/article/pii/004316489290160A

http://www.sciencedirect.com/science/article/pii/S0007850607622732

http://www.sciencedirect.com/science/article/pii/S0890695507002441

Thank you for the replies. Dr. Agri and Dr. Krahmer, how can I correlate the chip formation with the machining parameters?

Thank you Ali for the comprehensive responses

Can be a good work to correlate chip formation with tool shape, with cutting parameters.

Here I attach the table of differents chips shapes (from ISO 3685).

I think is possible to study, Which type of alloy for the cutting tool is exactly suitable for the product that want to produce, for Example to check the hardness for cutting tool and product, and geometery of the cutting tool

during turning operation, there are two possible cases one is formation of chatter or the other no formation of chatter. during chatter formation, there is vibration and more heat developed in the machined surface and in turn for the chip. due to this discontinious chips are formed and in turn effect cutting tool. For no formation of chatter, the chips formation maybe continious and does not effect much on tool.  I think this is a small idea where u can llok upon 

good luck