Instructors‘SolutionManual
THESCIENCE
ANDENGN I EERN
IG
OFMATERIALS
FourthEdition
The Science And Engineering Of Materials, Instructors
Solution Manual 4Th, Askeland
,
,Instructors‘SolutionManual
THESCIENCE
ANDENGN I EERN
IG
OFMATERIALS
FourthEdition
Donald R. Askeland
Pradeep P. Phulé
Prepared by Gregory Lea
The Science And Engineering Of Materials, Instructors
Solution Manual 4Th, Askeland
, 1
IntroductiontoMaterialsScience
andEngineering
1–5 Iron is often coated with a thin layer of zinc if it is to be used outside. What charac-
teristics do you think the zinc provides to this coated, or galvanized, steel? What
precautions should be considered in producing this product? How will the recycla-
bility of the product be affected?
Solution: The zinc provides corrosion resistance to the iron in two ways. If the
iron is completely coated with zinc, the zinc provides a barrier between
the iron and the surrounding environment, therefore protecting the
underlying iron. If the zinc coating is scratched to expose the iron, the
zinc continues to protect the iron because the zinc corrodes preferentially
to the iron (see Chapter 22). To be effective, the zinc should bond well
to the iron so that it does not permit reactions to occur at the interface
with the iron and so that the zinc remains intact during any forming of
the galvanized material. When the material is recycled, the zinc will be
lost by oxidation and vaporization, often producing a “zinc dust” that
may pose an environmental hazard. Special equipment may be required
to collect and either recycle or dispose of the zinc dust.
1–6 We would like to produce a transparent canopy for an aircraft. If we were to use a
ceramic (that is, traditional window glass) canopy, rocks or birds might cause it to
shatter. Design a material that would minimize damage or at least keep the canopy
from breaking into pieces.
Solution: We might sandwich a thin sheet of a transparent polymer between two
layers of the glass. This approach, used for windshields of automobiles,
will prevent the “safety” glass from completely disintegrating when it
1
THESCIENCE
ANDENGN I EERN
IG
OFMATERIALS
FourthEdition
The Science And Engineering Of Materials, Instructors
Solution Manual 4Th, Askeland
,
,Instructors‘SolutionManual
THESCIENCE
ANDENGN I EERN
IG
OFMATERIALS
FourthEdition
Donald R. Askeland
Pradeep P. Phulé
Prepared by Gregory Lea
The Science And Engineering Of Materials, Instructors
Solution Manual 4Th, Askeland
, 1
IntroductiontoMaterialsScience
andEngineering
1–5 Iron is often coated with a thin layer of zinc if it is to be used outside. What charac-
teristics do you think the zinc provides to this coated, or galvanized, steel? What
precautions should be considered in producing this product? How will the recycla-
bility of the product be affected?
Solution: The zinc provides corrosion resistance to the iron in two ways. If the
iron is completely coated with zinc, the zinc provides a barrier between
the iron and the surrounding environment, therefore protecting the
underlying iron. If the zinc coating is scratched to expose the iron, the
zinc continues to protect the iron because the zinc corrodes preferentially
to the iron (see Chapter 22). To be effective, the zinc should bond well
to the iron so that it does not permit reactions to occur at the interface
with the iron and so that the zinc remains intact during any forming of
the galvanized material. When the material is recycled, the zinc will be
lost by oxidation and vaporization, often producing a “zinc dust” that
may pose an environmental hazard. Special equipment may be required
to collect and either recycle or dispose of the zinc dust.
1–6 We would like to produce a transparent canopy for an aircraft. If we were to use a
ceramic (that is, traditional window glass) canopy, rocks or birds might cause it to
shatter. Design a material that would minimize damage or at least keep the canopy
from breaking into pieces.
Solution: We might sandwich a thin sheet of a transparent polymer between two
layers of the glass. This approach, used for windshields of automobiles,
will prevent the “safety” glass from completely disintegrating when it
1
