Final Exam(14-1-2013)
Manufacturing 1

Dr- Abd Al-Kareem

  • Choose the correct answer : (30 marks )

1-The size of the dead zone :
a- increase when the friction force increases between Ram and billet
b- decrease when the friction force increase between Ram and Billet

c- increase when the friction force increase between Container and Billet

d- increase when the friction force decrease between Rolls

2-Sensitivety :
a- increase with temperature only

b- increase with strain rate only

c- increase with strain rate , decrease with temperature

d- increase with temperature , decrease with Strain rate

3- If we have a specimen with initial length L1 and initial Area A1 , the second specimen with initial length 2L1 and initial Area 2A1 in the tensile test , which statement is true :

a- Second one two times of the elongation of the first one.

b- Second one two times of the elongation percent of the first one.

c- Reduction in the Area is the same .

d- Second one two times of the reduction percent of the first one.

4- Spreading :
*increase in width during rolling (Self Studying )

5- Toughness :
a- increase with ductility , decrease with strength

b- decrease with ductility , increase with strength

c- increases with Both.

d- decrease with Both.

6-The constant Strain rate in wire drawing leads to :

a-constant velocity

b- consequently decrease velocity

c- consequently increase velocity

d- none of the above

7- camber is :

The measure of correct for roll deformation (Self studying …Please check it ^_*)

8- Hydrostatic extrusion :

Used for brittle materials

9- If Material have yield strength “Y”, and put it fluid with hydrostatic pressure “P” ,, the new yield strength :

1- “Y-P”

2-“P-Y”

3-“P+Y”
4-Y

10- Flash in Impression die forging used for :

*To fill die cavities. (Check it ^^)

11- In metal Forming :

Hot working with low strain rate

12- When the forward slip increase , then :

a- the drive motor torque decrease

b-the drive motor torque increase because of the friction force reversible

c-The Roll force increase

d- The Roll force decrease

13- Uniform elongation occur in :

a- In both elastic and plastic

b-elastic only

c- Plastic only

d- Between U.T.S and Fracture

14- Which Statement is true for Poisson ratio :

a- in elastic from .2-.3 , in plastic equal .5

b- in elastic .2-.3 , in plastic does not exist

c- in elastic does not exist , in plastic equal .5

d- in elastic .2-.3 , in plastic more than .5

15- In the extrusion operation :

*Friction increase when the die angle decrease

  • Question about Roll Pressure (20 marks) :

Initial Volume of the specimen = 40x120x300 mm^3

Then the thickness decrease to be 25 mm

*Maximum Shear stress

Sigma= 400 €^(.7)

µ= .5

α= 15°

Roll radius = 1 m

Find the Roll pressure when ∆h= .5∆h(total ) ?