Chapter 5 Flashcards
Grain growth can be retarded by the use of which of the following methods? (Multiple Choice)
Question options:
A) Using small amounts of micro alloying elements such as zirconium or titanium
B) Retarding cooling in the ferrite range by use of stepped cooling in a furnace
C) Holding at high temperatures in the austenitizing range, cool, and furnace cool
D) Add gases such as oxygen and carbon dioxide to the melt and slow coo
A) Using small amounts of micro alloying elements such as zirconium or titanium
The ductility measured through the thickness of the plate is usually the lowest of all. The welding of large heavily restraint tee joints may therefore result in: (Multiple Choice)
Question options:
A) ductile tearing.
B) lamellar tearing.
C) hydrogen tearing.
D) brittle tearing.
B) lamellar tearing.
There are several metallurgical phases in a steel depending on its carbon content and heating history. How is ferrite best described? (Multiple Choice)
Question options:
A) A complex phase that occurs above 723 °C
B) A phase that depends on fulfilling its structure by fast cooling
C) A solid solution in a face-centered cubic (FCC) phase of iron that dissolves only small amounts of carbon
D) A solid solution in a body-centred cubic (BCC) phase of iron that dissolves very small amounts of carbon
A) A complex phase that occurs above 723 °C
What is a prime requirement when purchasing steel? (Multiple Choice)
Question options:
A) No requirement
B) The thickness
C) The physical properties
D) The steel specifications
D) The steel specifications
Which one of the following elements influences the shifting of lines in the phase diagram of steel to a point where steel becomes 100% austenite? (Multiple Choice)
Question options:
A) Nickel
B) Silicon and oxygen
C) Chromium and sulphur
D) Carbon
A) Nickel
Grain boundaries are the regions where atoms are in perfect order. (True/False)
Question options:
True
False
False
Two examples of grain refining elements are: (Multiple Choice)
Question options:
A) aluminum and vanadium.
B) oxygen and aluminum.
C) vanadium and oxygen.
D) carbon and aluminum.
A) aluminum and vanadium.
What is taconite? (Multiple Choice)
Question options:
A) it is coke
B) it is iron ore
C) it is cast iron
D) it is cementite
B) it is iron ore
The best elements in a drill bit in order to maintain resistance to tempering should be: (Multiple Choice)
Question options:
A) carbon and silicon.
B) chromium and tungsten.
C) nickel and cobalt.
D) vanadium and nickel.
B) chromium and tungsten.
A typical temperature for thermal stress relief treatment of welded fabrication is in the region of: (Multiple Choice)
Question options:
A) 225 °C
B) 425 °C
C) 625 °C
D) 825 °C
C) 625 °C
Resistance to tempering is a term that describes a material’s ability to retain: (Multiple Choice)
Question options:
A) ductility at high temperature.
B) hardness at high temperature.
C) chemical composition at high temperature.
D) grain structure at high temperature.
B) hardness at high temperature.
If more than 0.8% carbon is added to iron: (Multiple Choice)
Question options:
A) the resulting steel can no longer be forged.
B) the resulting material is called cast iron.
C) the resulting material will contain cementite and pearlite.
D) the resulting material will contain martensite and pearlite.
C) the resulting material will contain cementite and pearlite.
What can occur in large heavily restrained T-joints if a steel has poor ductility in the through-thickness direction? (Multiple Choice)
Question options:
A) Hot cracking in a lamellar mode and associated with the heat-affected zone microstructure
B) Tearing of the plate at the fusion line in a lamellar mode
C) Hydrogen assisted cold cracking in the weld
D) Lamellar tearing occurring in the parent plate
Which elements are added to molten steel specifically for deoxidation purposes? (Multiple Choice)
Question options:
A) Manganese and oxygen
B) Silicon and oxygen
C) Manganese and aluminum
D) Carbon and manganese
B) Silicon and oxygen
How is the yield point phenomenon explained? (Multiple Choice)
Question options:
A) The natural resistance of metals to external force
B) Dislocations are pinned by interstitial atoms
C) The displacement of atoms
D) None of the above
A) The natural resistance of metals to external force
Why are silicon and/or aluminum added to steel? (Multiple Choice)
Question options:
A) They are added to increase the carbon content
B) They are added to increase the grain size of the steel
C) They are added to remove dissolved oxygen
D) They are added to reduce the toughness of steel
C) They are added to remove dissolved oxygen
Elements commonly used to form substitutional solid solutions include: (Multiple Choice)
Question options:
A) nitrogen.
B) carbon.
C) copper.
D) oxygen.
B) carbon.
When a pressure vessel is made from formed plates, they are usually arranged: (Multiple Choice)
Question options:
A) with the rolling direction around the circumference.
B) with the rolling direction in a pattern alternating between around the circumference and along the length of the pipe.
C) with the rolling direction along the length of the pipe.
D) randomly.
A) with the rolling direction around the circumference.
The first step in converting iron ore into steel is the production of pig iron in the: (Multiple Choice)
Question options:
A) iron furnace.
B) smelt furnace.
C) electric furnace.
D) blast furnace.
D) blast furnace.
If more than 1.7% carbon is added to iron: (Multiple Choice)
Question options:
A) the resulting steel can no longer be forged.
B) the resulting material is called cast iron.
C) the resulting material will contain cementite and pearlite.
D) the resulting material will contain martensite and pearlite.
B) the resulting material is called cast iron.
When designing a steel to improve its hardenability and thus its strength, what is the normal approach? (Multiple Choice)
Question options:
A) Increase the grain size of the steel
B) Use a heat treatment that is guided by the mill followed by a stress relief.
C) Use a small amount of several hardening elements as the effect is better than using a single element
D) Use a single element such as carbon which has great hardenability and improves the weldability of the steel
C) Use a small amount of several hardening elements as the effect is better than using a single element
What are the three main components when charging a blast furnace? (Multiple Choice)
Question options:
A) Iron ore, nickel pellets, and limestone.
B) Iron ore, manganese ore, and coke
C) Iron ore, limestone, and coke
D) Iron ore, nickel pellets, and coke
C) Iron ore, limestone, and coke
Iron can change its crystallographic form as temperature changes. What form does iron take at a temperature of 250 degrees Celcius? (Multiple Choice)
Question options:
A) The body-centered cubic ferrite lattice form
B) The face-centered cubic austenite lattice form
C) The close-packed hexagonal delta lattice form
D) The distorted lattice form known as pearlite
Iron can change its crystallographic form as temperature changes. What form does iron take at a temperature of 250 degrees Celcius? (Multiple Choice)
Question options:
A) The body-centered cubic ferrite lattice form
B) The face-centered cubic austenite lattice form
C) The close-packed hexagonal delta lattice form
D) The distorted lattice form known as pearlite
5.2
A) The body-centered cubic ferrite lattice form
