Types Of Chips

The machining of metals highly depends on the types of chips it produces. When compared to the different production of metal, the metal is removed in various industries while doing the machining process is known as metal chips.

You may wonder what is actually machining process stands for? In simple words, the machining process is a cutting process in which the workpiece is cut by means of a tool to make its desired shape and size.

In this process, the excess metal of the workpiece is removed in the form of chips. The types of chips formed in the machining process depend on some basic factors. In machining, the formation of chips is a necessary index because it indicates directly or indirectly the:

1. Nature and behavior of the material under the machining process.

2. Nature and degree of interaction in chip interfaces.

3. The amount of energy required to extract the material.

What Are Some Conditions To Produce Chips?

1. Nature of material or workpiece

2. Material of cutting tool or Nature of tool

3. Level of decreasing velocity and feed rate

4. Machining environments like temperature

5. Cutting fluid

6. Dimension of tool

7. Friction between tool and work metal

Types of Chips

Types of chips in metal cutting are as follows:

1. Continuous chips

2. Discontinuous or segmented chips

3. Continuous chips with built-up edges

2. Discontinuous or Segmented Chips

In the machining process, the chips formed in a small segment or with breakage during cutting are known as discontinuous or segmented chips. Discontinuous chips are formed by using brittle or hard material in machining.

Brass, bronze, and cast iron are brittle materials. Due to slow cutting speed and small rack angle, this type of chip is produced. These chips are made when the friction between the tool and the workpiece is high.

Discontinuous chips in ductile materials provide a poor surface finish. The discontinuous chips are easily handled and disposed of.

How do discontinuous chips form during machining?

1. Due to the low feed rate in the machining process.

2. The cutting speed of the machining is low.

3. High friction between chip and tool face.

4. Due to the large depth of cut.

5. The rake angle of the tool is small.

Advantages of Discontinuous Chips

1. These types of chips provide a good surface finish in brittle materials.

2. It gives a long lifespan to the tool.

3. It reduces the consumption of power.

Disadvantages of Discontinuous Chips

1. By using ductile material, it gives a poor surface finish.

2. Excessive wear and tear of equipment occur.

3. Continuous Chips With Built-Up Edges

In the machining process of ductile material, continuous chips are made with built-up edges when the temperature and pressure in the cutting and friction of the chip and tool face are high.

It is almost similar to the continuous chips but it is rough due to the built-up edge. This function may cause the material to stick or weld to the edge of the tool.

You may wonder how it produces?

It is created, when the chip flows upward and friction between the interface of the chip and tool is high. The heat generated at the nose of the tool is very high, due to the high friction between the chip and the tool.

Hence, compressed metal fit to the tool nose is welded therefore it is known as built-up edges. If the chip flows through this built-up edge, it breaks and is sent away from the chip and is termed a built-up edge chip. The rest of the built-up edge adheres to the surface of the workpiece and does it thicker.

Why do Continuous Chips With BUE occur when you machine?

1. By using the ductile material while machining.

2. Due to the smaller rake angle of the tool.

3. The cutting speed of the tool is slow.

4. Lack of coolant may cause increases in friction between chip-tool faces.

5. The thickness of the chip is high.

6. Due to the high temperature between the workpiece and tool.

7. High rate of feed of the tool.

Advantages of Continuous Chips with BUE

1. Due to the high friction, while machining, it protects the tool from damage.

2. Also, it increases the tool lifespan.

Disadvantages of Continuous Chips with BUE

1. The drawback of this type of chip is that it provides a rough surface finish.

2. It may cause a reduction in rake angle and cutting forces.