High stiffness and strength
can be alloyed for high rigidity, strength, and hardness
Toughness
capacity to absorb energy better than other classes of materials
Good electrical conductivity
metals are conductors
Good thermal conductivity
conduct head better than ceramics or polymers
Cost
the price of steel is very competitive with other engineering materials
Cast metal
starting form is a casting
Wrought metal
the metal has been worked or can be worked after casting
Powdered metal
starting form is very small powders for conversion into parts using powder metallurgy techniques
Ferrous
Those based on iron, steels, cast irons
Nonferrous
all other metals, aluminum, magnesium, copper, nickel, titanium, zinc, lead, tin, gold, silver
Alloy
a mixture or compound of two or more elements, at least one of which is metallic
The phase of Iron at room temperature
alpha, α, called ferrite
What does ferrite transform to as temperature rises?
Ferrite, alpha, to austenite, gamma, to delta
Steel
an iron-carbon alloy containing from 0.02% to 2.1% carbon
Cast iron
an iron-carbon alloy containing from 2.1% to about 4% or 5% carbon
Ductile iron
is formed by special melting and pouring treatment of gray cast iron
Malleable iron
is formed by heat treatment of white cast iron
THIS IS START OF CH 6 ASSIGNMENT
IGNORE
What are some of the general properties that distinguish metals from ceramics and polymers?
Typical metallic properties include: high strength and stiffness, good electrical and thermal conductivity, and higher density than ceramics or polymers
What are the two major groups of metals? Define them.
Ferrous metals, which are based on iron; and nonferrous, which includes all others.
What is a solid solution in the context of alloys?
A solid solution is an alloy in which one of the metallic elements is dissolved in another to form a single phase.
Distinguish between a substitutional solid solution and an interstitial solid solution.
A substitutional solid solution is where the atoms of the dissolved element replace atoms of the solution element in the lattice structure of the metal. An interstitial solid solution is where the dissolved atoms are small and fit into the vacant spaces (the interstices) in the lattice structure of the solvent metal.
What is an intermediate phase in the context of alloys?
An intermediate phase is an alloy formed when the solubility limit of the base metal in the mixture is exceeded and a new phase, such as a metallic compound (e.g., Fe3C) or intermetallic compound (e.g., Mg2Pb) is formed.
What is the range of carbon percentages that defines an iron‑carbon alloy as a steel?
The carbon content ranges from 0.02% to 2.11%.
What is the range of carbon percentages that defines an iron‑carbon alloy as cast iron?
The carbon content ranges from 2.11% to about 5%.
Identify some of the common alloying elements other than carbon in low alloy steels.
The common alloying elements in low alloy steel are Cr, Mn, Mo, Ni, and V. at least two
What is the predominant alloying element in all of the stainless steels?
Chromium
Besides high carbon content, what other alloying element is characteristic of the cast irons?
Silicon
Identify some of the properties for which aluminum is noted?
Aluminum is noted for its low density, high electrical and thermal conductivity, formability, good corrosion resistance due to the formation of a tough oxide film on its surface, and ability to be alloyed and strengthened to achieve good strength‑to‑weight ratios.
What are some of the noteworthy properties of magnesium?
Magnesium is noted for its very low density (lightest of the structural metals), propensity to oxidize (which can cause problems in processing), and low strength; however, it can be alloyed and strengthened by methods similar to those used for aluminum alloys to achieve respectable strength‑to‑weight ratios
What is the most important engineering property of copper that determines most of its applications?
Its high electrical conductivity (low resistivity).
What elements are traditionally alloyed with copper to form (a) bronze and (b) brass?
The elements are (a) tin and (b) zinc, respectively.
What are some of the important applications of nickel?
The important applications of Ni are (1) as an alloying ingredient in steel, e.g., stainless steel; (2) for plating of steel to resist corrosion; and (3) to form nickel‑based alloys noted for high‑temperature performance and corrosion resistance
What are the noteworthy properties of titanium?
Titanium is noted for its high strength‑to‑weight ratio, corrosion resistance (due to the formation of a thin but tough oxide film), and high temperature strength.
Identify some of the important applications of zinc.
The important applications of Zn are (1) die castings ‑ zinc is an easy metal to cast; (2) as a coating in galvanized steel; (3) as an alloying element with copper to form brass.
What important alloy is formed from lead and tin?
Solder
What is so special about the superalloys? What distinguishes them from other alloys?
The superalloys are generally distinguished by their strength and resistance to corrosion and oxidation at elevated temperatures.
What are the three basic methods by which metals can be strengthened?
The three basic methods are (1) alloying to form solid solutions and two‑phase structures which are stronger than the elemental metals; (2) cold working, in which the strain‑hardened metal is stronger and harder than the unstrained metal; and (3) heat treatment ‑ most of the commercial heat treatments are designed to increase the strength of the metal.
THIS IS START OF CH 21 SLIDES
IGNORE
Machining
a material removal process in which a sharp cutting tool is used to mechanically cut away material so that the desired part geometry remains
Turning
Facing
Contour Turning
instead of feeding tool parallel to axis of rotation, tool follows a contour that is other than straight, thus creating a contoured shape
Chamfering
cutting edge cuts an angle on the corner of the cylinder, former a chamfer
Cutoff
tool is fed radically into rotating work at some location to cut off end of part
threading
pointed form tool is fed linearly across surface of rotating work part parallel to axis of rotation at a large feed rate, thus creating threads
MANUAL LATHE
Reaming
tapping
counterboring
countersinking
center drilling
spot facing
DRILL PRESS
Vertical milling machine
THIS IS START OF CH 6 QUIZ
RECHECK ANSWERS
Sand casting is which of the following types:
expendable mold
The upper half of a sand casting mold is called which of the following:
cope
In foundry work, a runner is which one of the following:
channel in the mold leading from the downsprue to the main mold cavity
A riser in casting is NOT described by which of the following:
an insert in the casting that inhibits buoyancy of the core
Which one of the following casting processes is the most widely used:
sand casting
For which one of the following reasons is a green mold named:
moisture is contained in the mold
Shell molding is best described by which one of the following:
casting process in which the mold is a thin shell of sand binded by a thermosetting resin
Which of the following qualifies as a precision casting process:
investment casting
Which of the following metals would typically be cast in die casting
aluminum
A misrun is which one of the following defects in casting:
metal solidifies before filling the cavity
START OF CH 39 40
The manufacturing engineering department in an organization is best described as which one of the following:
technical staff function
Which of the following is NOT a usual responsibility of the manufacturing engineering department?
marketing the product
Which of the following is considered a basic process, as opposed to a secondary process?
impression die forging
Which of the following would be considered a secondary process, as opposed to a basic process?
machining a metal casting
In a make or buy situation, the decision should always be to purchase the component if the vendor ’s quoted price is less than the in-house estimated cost of the component:
False
Which of the following is an operation to enhance physical properties?
annealing
A route sheet is a document whose principal function is which one of the following?
specifies the process plan
Which one of the following types of computer-aided process planning relies on parts classification and coding in group technology?
retrieval CAPP
Start of Jeopardy
jeopardy
For what is aluminum not noted
poor corrosion resistance. Has good corrosion resistance
CHECK PHOTOS
RANGE OF CARBON PERCENTAGES
the distance the tool advances into or along the workpiece each time the tool point passes a certain position in its travel over the surface is called
Feed
Ch 21 quiz
ch 21 quiz
In a turning operation, the change in diameter of the workpart is equal to which one of the following:
2 x depth of cut
A lathe can be used to perform which of the following machining operations:
boring
A facing operation is normally performed on which one of the following machine tools:
lathe
Knurling is performed on a lathe, but it is a metal forming operation rather than a metal removal operation:
true
Which one of the following cutting tools cannot be used on a turret lathe:
broach
Which one of the following turning machines permits very long bar stock to be used:
screw machine
Reaming is used for which of the following functions:
enlarge a drilled hole
End milling is most similar to which one of the following:
face milling
A planing operation is best described by which one of the following:
a workpart moves linearly past a single-point tool
A broaching operation is best described by which one of the following:
a tool with multiple teeth moves linearly past a stationary workpart