Materials 2

Dpt. Materials Science and Eng. and Chemical Eng.
Aerospace Materials II

Questions on Metallic Materials:  
Topic 2: Solidification of Metals. Metal Casting Processes  Topic 3: Metal Forming Fundamentals. Metals Forming Processes 
1. Three pieces being cast have the same volume but different shapes. One is a sphere, one
is a cube, and other a cylinder with a height equal to its diameter. Ifeach cast is using a
cylindrical riser, will each part require the same size riser to ensure proper feeding?
2. A cooling curve is shown in figure below. Determine:
a. the pouring temperature
b.the solidification temperature
c. the superheat
d. the cooling rate, just before solidification begins
e. the total solidification time
f. the local solidification time
g. if the cooling curve wasobtained at the centre of a casting cube casting
(50mmX50mmX50mm), determine the mold constant, assuming the n=2

3. We know that pouring metal at a high rate into a mold has certaindisadvantages. Are
there any disadvantages to pouring it very slowly?
4. Is there any difference in the tendency for shrinkage void formation for metals with short
and long freezing ranges, respectively?Explain.
5. Sketch a graph of specific volume versus temperature for a metal that shrinks as it cools
from the liquid state to room temperature. On the graph, mark the area where shrinkage is
compensatedfor by risers.
6. How can you tell whether cavities in a casting are due to shrinkage or entrained air
bubbles?
7. A cylinder with a diameter of 1 in. and height of 3 in. solidifies in threeminutes in a sand
casting operation. What is the solidification time if the cylinder height is doubled? What
is the time if the diameter is doubled?

ATTENTION: The answers are not valid if they arenot justified accordingly. Justifying and
defending an answer is more important.

1

Dpt. Materials Science and Eng. and Chemical Eng.
Aerospace Materials II

8. A rectangular mold with...