TYPES OF CHIPS-
There are three common types of chips. They are as follows-
The types of chips can be identified just by observing the picture posted below-
1. Discontinuous or segmental chips-
These types of chips are usually seen with the characteristics of a series of ruptures which is nearly perpendicular to the tool face, each and every chip element passing along or near to the tool in the form of small segments. Sometimes these ruptures may last for a certain length. We know that the chips break into smaller segments or parts due to the friction between the tool and the chips. This results in better surface finishing.
Discontinuous chips are those chips that break into many pieces while chipping. Discontinuous chips are mainly found to be formed for brittle materials such as cast iron and bronze, large chip thickness, low cutting speed and small rack angle.
2. Continuous chips-
Continuous chips I usually formed without ruptures but by the continuous deformation of the metal without any fractures. The feed given by us drives the tool smoothly with the chip facing up the tool. There are some materials that provide continuous chips while machining. The best type of metals for continuous chips are mild steel and copper. The chips obtained with these materials have same thickness throughout the chip. The stability of this chip is more when compared to other chips and a very better surface finish can be obtained.
Continuous chips are found to be formed for the material that exhibit ductility. High cutting Speed, small chip thickness, large rake angle and friction of the chip and the tool are responsible for continuous chips.
3. Continuous chips with Built up Edge-
For both the continuous chips and discontinuous chips build up cannot be seen but can be seen very rare. These types of chips are usually continuous chips that former build up just after the chip has been formed. These are formed due to many characteristics namely the amount of feed applied, the type of material, ductility of the material, type of lubricant used and the rake angle. It also depends on the friction properties namely polished tool face, use of efficient cutting lubricants and use of tool material that have a low coefficient of friction. The Build up edge increases in the beginning of cutting operation and decreases as the process go on continuously.
These are the different types of chips.