PRIST UNIVERSITY, TRICHY CAMPUS, TRICHY - 9

PRIST UNIVERSITY

Department of Mechanical Engineering

M.Tech. Manufacturing Engineering I semester CONSOLIDATED QUESTION BANK

Subject: THEORY OF METAL CUTTING

PART A - (TWO MARK QUESTIONS)

UNIT - I

1. Define orthogonal cutting process.

2. What is oblique cutting?

3. List out geometry of a single point cutting tool.

4. Define chip thickness ratio.

5. What is chip velocity?

6. List out the assumptions made in merchants theory.

7. Define shear plane angle.

8. What is shear angle?

9. What is rake angle?

10. Differentiate between orthogonal and oblique cutting.

UNIT II1. Classify the types of chips.

2. What is meant by continuous chips?

3. What is chip reduction coefficient?

4. What is meant by built-up edge (BUE)?

5. Define chip breaker.

6. What way the chip formation affects the tool life?

7. Why is the chisel edge a problem area during a drilling operation?

8. . What are the different types of chip?

9. What are the various factors to affect the cutting tool?

10. What is the function of chip breaker?

UNIT III

1. Define the term Machinability.

2. Give the Taylors tool life equation.

3. Define machinability index.

4. List out the variables affecting the tool life

5. What are the main causes of tool wear?

6. What are the various methods to measure the tool wear?

7. What is plastic failure?

8. What is the purpose of tool life test?

9. Define tool life.

10. How is the tool wear measured?

UNIT IV1. What are factors to be considered to reduce the heat generation?

2. With a neat sketch, indicate the heat distribution zone in a machining operation.

3. State the law of successive temperatures.

4. How heat generation affects the tool life?

5. State the principle of photographic method?

6. Define thermodynamics of orthogonal cutting?

7. What are the various factors involved in heat generation during the metal cutting?

8. Write down various methods to reduce the heat generation?

9. What are the various defects due the heat generation in the work piece

10. Write down the various applications of thermocouple principles in metal cutting.

UNIT V1. What is meant by chatter?

2. What are the factors consider for the selection of tool materials?

3. What is CBN?

4. List out the properties of cutting tool materials.

5. What is meant by cermet?

6. What do you mean by alloy tool steel?

7. How will you avoid chatter in machining?

8. List out the various types of chatter?

9. What is lobbing diagram?

10. What is PCD?

PART B (16 MARKS QUESTIONS)UNIT I

1. Explain and derive the relationship for shear plane angle in orthogonal cutting.

2. Explain the Lee and Shafler theory.

3. List out the assumptions made in Merchant thing shear plane model. Explain the various forces acting in orthogonal cutting.

4. Explain the metal cutting theories in detail and explain any one of them.

5. An orthogonal cutting of steel is done with 10 rake tool, with a depth of cut 2mm and feed rate of 0.20 mm/rev. The cutting speed is 200m.min. The chip thickness ratio is 0.31. The vertical force is 1200N and the horizontal cutting force is 650N. Calculate shear plane angle, normal force on the shear plane, friction force and coefficient of friction.

6. Derive the relationship for shear plane angle in orthogonal cutting.

UNIT II

1. List out the various types of chips? Explain the chip formation mechanism.

2. Explain the effects of cutting variables of chip reduction coefficient.

3. Explain the chip formation in drilling operation.

4. Explain chip formation in milling operation.

5. Explain the nomenclature of a single point cutting tool with the help of a neat sketch.

UNIT III

1. Describe the different accelerated tool life tests.

2. Explain the mechanism of various types of wear.

3. Explain briefly the variables affecting the tool life.

4. During the machining of low carbon steel with HSS the following Observations were made:

Cutting speed, m/min4050

Tool life, minutes

4010

Express the values in tailors tool life equation form.

5. While machining carbon steel by a tungsten-cobalt steel tool it was observed that the tool life was 50mins, for a cutting speed of a 50m/min. Determine the tool life for a cutting speed of 40m/min, using Taylors tool life equation, taking the index n as 0.143.

UNIT IV1. Name various methods of temperature measurement in metal cutting and explain any one method in detail.

2. Explain thermodynamics of orthogonal cutting with a neat sketch.

3. Explain with a neat sketch, how the temperature is measured in metal cutting by emitted radiation method.

4. Explain with a neat sketch, how to analyse the temperature at the shear plane.

5. Explain three distinct sources of heat generated in metal cutting, Write equations to calculate the temperatures in the cutting zone.

6. Explain with a neat sketch, how to measure the temperature between tool and

workpiece by direct tool-work thermocouple method.

UNIT V1. Discuss the various factors that influence tool chatter and its effect on machining process.

2. Write short notes on various tool materials CBN, HSS, PCD and its applications

3. Write short notes on (a) Titanium carbide coating (b) Titanium nitride coating (c) Aluminum oxide coating

4. Describe the characteristics of a good tool material. List any five popular cutting tool materials their composition, properties and applications.5. Explain the various types of chatter on the work piece.