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Metal FormingMetal Forming

By  S K MondalCompiled By: S K Mondal                    Made Easy

IES 2011Assertion (A): Lead, Zinc and Tin are always hotworked.Reason (R) : If they are worked in cold statethey cannot retain theirmechanical properties.(a) Both A and R are individually true and R is the(a) Both A and R are individually true and R is thecorrect explanation of A(b) Both A and R are individually true but R is NOTthe correct explanation of A(c) A is true but R is false(d) A is false but R is true

Ans. (c)Compiled By: S K Mondal                    Made Easy

GATE‐2003 Cold working of steel is defined asworking(a) At its recrystallisation temperature(b) Above its recrystallisation temperature(c) Below its recrystallisation temperature(d) At two thirds of the melting temperature of themetal

Ans. (c)

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GATE‐2002Hot rolling of mild steel is carried out(a) At recrystallisation temperature(b) Between 100°C to 150°C(c) Below recrystallisation temperature(d) Above recrystallisation temperature

Ans. (d)

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IES – 2006Which one of the following is the process to refinethe grains of metal after it has been distorted byhammering or cold working?(a) Annealing (b) Softening( ) R t lli i (d) N li i(c) Re‐crystallizing (d) Normalizing

Ans. (c)

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IES – 2004Consider the following statements:In comparison to hot working, in cold working,1. Higher forces are required2. No heating is required3. Less ductility is required4. Better surface finish is obtainedWhich of the statements given above are correct?(a) 1, 2 and 3 (b) 1, 2 and 4(c) 1 and 3 (d) 2, 3 and 4

Ans. (b)Compiled By: S K Mondal                    Made Easy

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IES – 2009Consider the following characteristics:1. Porosity in the metal is largely eliminated.2. Strength is decreased.3. Close tolerances cannot be maintained.Which of the above characteristics of hot working is/arecorrect?(a) 1 only (b) 3 only(c) 2 and 3 (d) 1 and 3

Ans. (d)

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IES – 2008Consider the following statements:1. Metal forming decreases harmful effects ofimpurities and improves mechanical strength.2. Metal working process is a plastic deformationprocess.3. Very intricate shapes can be produced by forgingprocess as compared to casting process.Which of the statements given above are correct?(a) 1, 2 and 3 (b) 1 and 2 only(c) 2 and 3 only (d) 1 and 3 only

Ans. (b) Compiled By: S K Mondal                    Made Easy

IES – 2008Cold forging results in improved quality due towhich of the following?1. Better mechanical properties of the process.2. Unbroken grain flow.3. Smoother finishes.4. High pressure.Select the correct answer using the code given below:(a) 1, 2 and 3 (b) 1, 2 and 4(c) 2, 3 and 4 (d) 1, 3 and 4

Ans. (a)Compiled By: S K Mondal                    Made Easy

IES – 2004Assertion (A): Cold working of metals results inincrease of strength and hardnessReason (R): Cold working reduces the total numberof dislocations per unit volume of thematerial( ) B th A d R i di id ll t d R i th(a) Both A and R are individually true and R is thecorrect explanation of A(b) Both A and R are individually true but R is not thecorrect explanation of A(c) A is true but R is false(d) A is false but R is true

Ans. (c)Compiled By: S K Mondal                    Made Easy

IES – 2003Cold working produces the following effects:1. Stresses are set up in the metal2. Grain structure gets distorted3. Strength and hardness of the metal are decreased4. Surface finish is reducedWhich of these statements are correct?(a) 1and 2 (b) 1, 2 and 3(c) 3 and 4 (d) 1 and 4

Ans. (a)

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IES – 2000Assertion (A): To obtain large deformations by coldworking intermediate annealing is not required.Reason (R): Cold working is performed below therecrystallisation temperature of theworkmaterial.( ) B th A d R i di id ll t d R i th(a) Both A and R are individually true and R is thecorrect explanation of A(b) Both A and R are individually true but R is not thecorrect explanation of A(c) A is true but R is false(d) A is false but R is true

Ans. (d)Compiled By: S K Mondal                    Made Easy

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IES – 1997In metals subjected to cold working, strain hardening effect is due to(a) Slip mechanism(b) Twining mechanism(c) Dislocation mechanism(d) Fracture mechanism

Ans. (c)

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IES – 1996Consider the following statements:When a metal or alloy is cold worked1. It is worked below room temperature.2. It is worked below recrystallisation temperature.3 Its hardness and strength increase3. Its hardness and strength increase.4. Its hardness increases but strength does not increase.Of these correct statements are(a) 1 and 4  (b) 1 and 3 (c) 2 and 3  (d) 2 and 4

Ans. (c)Compiled By: S K Mondal                    Made Easy

IES – 2006Assertion (A): In case of hot working of metals, thetemperature at which the process is finally stoppedshould not be above the recrystallisation temperature.Reason (R): If the process is stopped above therecrystallisation temperature, grain growth will takeplace again and spoil the attained structureplace again and spoil the attained structure.(a) Both A and R are individually true and R is the correctexplanation of A(b) Both A and R are individually true but R is not thecorrect explanation of A(c) A is true but R is false(d) A is false but R is true

Ans. (d)Compiled By: S K Mondal                    Made Easy

IES – 1992Specify the sequence correctly(a) Grain growth, recrystallisation, stress relief(b) Stress relief, grain growth, recrystallisation(c) Stress relief, recrystallisation, grain growth(d) Grain growth, stress relief, recrystallisation

Ans. ( c)

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IAS – 1996Formild steel, the hot forging temperature range is(a) 4000C to 6000C(b) 7000C to 9000C(c) 10000C to 12000C(d) 13000Cto 15000C

Ans. (c)

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IAS – 2004Assertion (A): Hot working does not produce strain hardening.Reason (R): Hot working is done above the re‐crystallization temperature.( ) B th A  d R   i di id ll  t   d R i  th  (a) Both A and R are individually true and R is the correct explanation of A(b) Both A and R are individually true but R is not the correct explanation of A (c) A is true but R is false(d) A is false but R is true

Ans. (a)Compiled By: S K Mondal                    Made Easy

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IAS‐2002Assertion (A): There is good grain refinement in hotworking.Reason (R): In hot working physical properties aregenerally improved.( ) B th A d R i di id ll t d R i th(a) Both A and R are individually true and R is thecorrect explanation of A(b) Both A and R are individually true but R is not thecorrect explanation of A(c) A is true but R is false(d) A is false but R is true

Ans. (b)Compiled By: S K Mondal                    Made Easy IES Made EasyCompiled By: S K Mondal                    Made Easy