What is a discontinuous chip?
Discontinuous Chips If the chips formed during machining process is not continuous i.e. formed with breakage is called discontinuous chips. Discontinuous types of chips are formed when hard and brittle metals like brass, bronze and cast iron is machined.
What is discontinuous chip formation?
Discontinuous chips are formed when brittle or hard metals like brass, bronze and cast iron are used as workpiece in the machining process. Discontinuous chips are also formed in ductile material when the friction between tool and workpiece is high.
Which of the following factors result in to continuous chip formation?
The high cutting speed and large rake angle of the tool will result in the formation of continuous chips.
What are the consequences of a cutting tool chips?
21.22 What are the consequences if a cutting tool chips? By the student. Tool chipping has various effects, such as poor surface finish and dimensional control of the part being machined; possible temperature rise; and cutting force fluctuations and increases.
What causes discontinuous chips?
“Discontinuous Chip – Discontinuous or segmented chips are produced when brittle metal such as cast iron and hard bronze are cut or when some ductile metals are cut under poor cutting conditions.
What are the favorable factors for discontinuous chip formation?
Discontinuous chip
- Hard and brittle work material.
- The workpiece is having hard inclusion and impurities.
- Low speed.
- High feed rate.
- High depth of cut.
- Low back rake angle.
- High friction.
- Low stiffness of machine tools that allows vibrations.
What are the factors which affect the formation of continuous chip and discontinuous chip?
Continuous chips:
- Factors that affect continuous chips.
- Ductile metal.
- High machining speed.
- Large rake angle.
- Sharp cutting edge.
- Efficient cooling fluid.
- Low friction between tool face and chips.
Which type of the chips usually results in the poorest surface finish?
Discontinuous chips result in poor surface finish and fluctuation of cutting forces.
Do you think that there is a relationship between the cost of a cutting tool and its hot hardness explain?
22.34 Do you think that there is a relationship between the cost of a cutting tool and its hot hardness? Explain. Generally, as hot hardness increases, the cost of the tool material increases. For example, ce- ramics have high hot hardness and are generally made of inexpensive raw materials.
What is chipping in mechanical engineering?
Chip formation is part of the process of cutting materials by mechanical means, using tools such as saws, lathes and milling cutters. Chip formation is usually described according to a three-way model developed by Franz.
Why are discontinuous chips preferred over continuous chips?
As most of the heat generated carried out by the chip, temperature at the edge of tool is less, and longer life of tool is the result. For brittle material, discontinuous chip gives a fair surface finish, lower power consumption and increase tool life. Discontinuous chips are convenient to handle and dispose of.
Which of the following is a condition for discontinuous chip?
Cause of formation of discontinuous chip: Highly brittle material of work piece. Smaller bevel of cut tools. Lower cutting speed. Large feed, thick chip.
Which is better discontinuous chip or brittle chip?
For brittle material, discontinuous chip gives a fair surface finish, lower power consumption and increase tool life. But in ductile materials, it causes a poor surface finish and excessive tool wear.
Why are discontinuous chips used in ductile materials?
For brittle material, discontinuous chip gives a fair surface finish, lower power consumption and increase tool life. But in ductile materials, it causes a poor surface finish and excessive tool wear. Discontinuous chips are convenient to handle and dispose of.
How are discontinuous chips formed in metal cutting?
Discontinuous chips are also produced when cutting more ductile material with the use of a cutting fluid. Continuous chips are formed by the continuous plastic deformation of metal without fracture in front of the cutting edge of the tool and is formed by the smooth flow of the chip up the tool face.
What makes discontinuous chips look like Sawtooths?
But in ductile materials, it causes a poor surface finish and excessive tool wear. Discontinuous chips are convenient to handle and dispose of. They are semi-continuous chips formed due to non-uniform strain on the material during cutting. It has sawtooth-like appearance due to zones of low and high shear strain.