ENG MAT EXAM 6-...

Besides high carbon content, what other alloying element is characteristic of the cast irons?

Silicon

What important alloy is formed from lead and tin?

Solder

In a turning operation, the change in diameter of the workpart is equal to which one of the following:

2 x depth of cut

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.

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. At least two

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.

A lathe can be used to perform which of the following machining operations:

Boring

What is the predominant alloying element in all of the stainless steels?

Chromium

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 the most important engineering property of copper that determines most of its applications?

Its high electrical conductivity (low resistivity).

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. At least two

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 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. At least two

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. At least two

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.

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. At least two.

Knurling is performed on a lathe, but it is a metal forming operation rather than a metal removal operation:

True

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. At least two of these

A broaching operation is best described by which one of the following:

a tool with multiple teeth moves linearly past a stationary workpart

A planing operation is best described by which one of the following:

a workpart moves linearly past a single-point tool

Which one of the following cutting tools cannot be used on a turret lathe:

broach

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 facing operation is normally performed on which one of the following machine tools:

lathe

Which one of the following turning machines permits very long bar stock to be used:

screw machine