|
Characteristics and Properties of Metals
A.
Bhatia
Overview
The
understanding of the structure and properties of metals, stress mechanisms,
failure modes and the characteristics determine
their usefulness for a specific application. Often, materials
are subject to variable forces (loads). The mechanical engineer calculates these
forces to establish the service that can be expected and material scientists
experiment to determine how materials deform (elongate, compress, and twist) or
break as a function of applied load, time, temperature, and other conditions.
Metals typically exhibit crystalline structure and have three
most common crystal patterns: (1) the body-centered cubic (BCC), (2) the
face-centered cubic (FCC) and (3) the hexagonal closed packed (HCP).
-
Metals containing BCC structures include ferrite, chromium,
vanadium, molybdenum, and tungsten. These metals possess high strength and low
ductility.
-
Metals containing FCC structures include austenite, aluminum,
copper, lead, silver, gold, nickel, platinum and thorium. These metal possess
low strength and high ductility.
-
Metals containing HCP structures include beryllium, magnesium,
zinc, cadmium, cobalt, thallium and zirconium. These metals are not as ductile
as FCC metals.
Mechanical properties are also used to help specify and identify
metals. The most common properties considered are strength, hardness, ductility,
and impact resistance. Understanding the basic properties of metals is critical
in identifying the most appropriate metal to use for each application.
This
8-hr course explains the basic structure of metals and describes how those structures are
affected by various processes. The course is
based entirely on US Department of Energy
training materials DOE-HDBK-1017/1-93,
Fundamentals Handbook, Material Science; Volume 1 of 2. It
contains two modules 1 and 2:
-
Module 1, "Structure of Metals" contains
information on the basic structure of metals and discusses various
imperfections and defects that affect metals.
-
Module 2, "Properties of Metals" contains
information on the properties of metals to be considered when selecting
materials for a particular application.
The student must take a multiple-choice quiz consisting of
forty (40) questions at the end of
this course to obtain PDH credits.
Specific Knowledge or Skill Attained
This course teaches the following specific knowledge and
skills:
-
The
nature of
five
types of bonding that occur in materials and their characteristics.
-
The
three most common types of crystalline structures : Body-centered cubic
structure, Face-centered cubic structure and Hexagonal close-packed structure
-
The
three types of microscopic imperfections found in crystalline structures.
-
How to
distinguish between tensile, compressive and shear stresses
-
Understand the following terms: a) Strain, b) Plastic deformation, c)
Proportional limit, d) Yield point, e) Ultimate strength and f) Fracture point
-
Hooke's Law and Young’s Modulus (Elastic Modulus) as it relates to stress.
-
How to
interpret a stress-strain curve for the following: a) Application of Hooke's
Law, b) Elastic region and c) Plastic region
-
The
important mechanical properties of metals such as a) Strength, b) Ultimate
tensile strength, c) Yield strength, d) Ductility, e) Malleability, f)
Toughness and g) Hardness
-
The
effects on ductility caused by temperature changes, irradiation and cold
working
-
How
heat treatment affects the properties of heat-treated steel and carbon steel.
-
The
reason that galvanic corrosion is a concern in design and material selection.
-
Hydrogen embitterment including the two required conditions and the formation
process.
Course
Click on the following
PDF attachment and review the document prior to taking a quiz for credit.
Characteristics and Properties of Metals (1.5 MB)
Having Trouble Downloading the PDF File?
Right click on the link. Select "Save Target As..."
Then save on your desktop. To view the file, double click the icon on your
desktop and return to this page to take the quiz.
You may need Acrobat Reader to view this document.
Click on the link below to download a free copy of Acrobat Reader.
To obtain PDH credits for this course, you will need to take a quiz for
credit. Click on the link below.
(To take the quiz,
your web browser must be set to accept cookies. See how to
check your cookie settings.)
 
|
|
|
Related Books
Metals Handbook
Mechanical
Metallurgy
Physical
Metallurgy
Fundamentals
of Physical Metallurgy
 |
|
