Question & Answer

Using the lead-tin phase diagram in Figure 6.3, determine the liquid and solid phase compositions for a nominal composition of 40% Sn and 60% Pb at 204°C (400°F).

For the preceding problem, use the inverse lever rule to determine the proportions of liquid and solid phases present in the alloy.

For the copper-nickel phase diagram in Figure 6.2, find the compositions of the liquid and solid phases for a nominal composition of 70% Ni and 30% Cu at 1371°C (2500°F).

There are 20 correct answers in the following multiple choice questions (some questions have multiple answers that are correct). To attain a perfect score on the quiz, all correct answers must be given. Each correct answer is worth 1 point. Each omitted answer or wrong answer reduces the score by 1 point, and each additional answer beyond the correct number of answers reduces the score by 1 point. Percentage score on the quiz is based on the total number of correct answers.

6.1 Which of the following properties or characteristics are inconsistent with the metals (two correct answers): (a) good thermal conductivity, (b) high strength, (c) high electrical resistivity, (d) high stiffness, and (e) ionic bonding?

6.2 Which one of the metallic elements is the most abundant on the earth: (a) aluminum, (b) copper, (c) iron, (d) magnesium, or (e) silicon?

6.3 The predominant phase in the iron-carbon alloy system for a composition with 99% Fe at room temperature is which one of the following: (a) austenite, (b) cementite, (c) delta, (d) ferrite, or (e) gamma?

6.4 A steel with 1.0% carbon is known as which one of the following: (a) eutectoid, (b) hypoeutectoid, (c) hypereutectoid, or (d) wrought iron?

6.5 The strength and hardness of steel increases as carbon content (a) increases or (b) decreases?

6.6 Plain carbon steels are designated in the AISI code system by which of the following: (a) 01XX, (b) 10XX, (c) 11XX, (d) 12XX, or (e) 30XX?

6.7 Which one of the following elements is the most important alloying ingredient in steel: (a) carbon, (b) chromium, (c) nickel, (d) molybdenum, or (e) vanadium?

6.8 Which one of the following is not a common alloying ingredient in steel: (a) chromium, (b) manganese, (c) nickel, (d) vanadium, (e) zinc?

6.9 Solid solution alloying is the principal strengthening mechanism in high-strength low-alloy (HSLA) steels: (a) true or (b) false?

6.10 Which of the following alloying elements are most commonly associated with stainless steel (two best answers): (a) chromium, (b) manganese, (c) molybdenum, (d) nickel, and (e) tungsten?

6.11 Which of the following is the most important cast iron commercially: (a) ductile cast iron, (b) gray cast iron, (c) malleable iron, or (d) white cast iron?

6.12 Which one of the following metals has the lowest density: (a) aluminum, (b) magnesium, (c) tin, or (d) titanium.?

6.13 Which of the following metals has the highest density: (a) gold, (b) lead, (c) platinum, (d) silver, or (e) tun

gsten?

6.14 From which of the following ores is aluminum derived: (a) alumina, (b) bauxite, (c) cementite, (d) hematite, or (e) scheelite?

6.15 Which of the following metals is noted for its good electrical conductivity (one best answer): (a) copper, (b) gold, (c) iron, (d) nickel, or (e) tungsten?

6.16 Traditional brass is an alloy of which of the following metallic elements (two correct answers): (a) aluminum, (b) copper, (c) gold, (d) tin, and (e) zinc?

6.17 Which one of the following metals has the lowest melting point: (a) aluminum, (b) lead, (c) magnesium, (d) tin, or (e) zinc?

What are the three basic methods by which metals can be strengthened?

What is so special about the superalloys? What distinguishes them from other alloys?

The superalloys divide into three basic groups, according to the base metal used in the alloy. Name the three groups

(a) Name the four principal noble metals. (b) Why are they called noble metals?

(a) Name the important refractory metals. (b) What does the term refractory mean?

What important alloy is formed from lead and tin?

Identify some of the important applications of zinc.

What are the noteworthy properties of titanium?

What are some of the important applications of nickel?

What elements are traditionally alloyed with copper to form (a) bronze and (b) brass?

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

What are some of the noteworthy properties of magnesium?

Identify some of the properties for which aluminum is noted?

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

Why is austenitic stainless steel called by that name?

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

What are some of the mechanisms by which the alloying elements other than carbon strengthen steel?

Identify some of the common alloying elements other than carbon in low alloy steels.

What is the range of carbon percentages which defines an iron-carbon alloy as cast iron?

What is the range of carbon percentages which defines an iron-carbon alloy as a steel?

The copper-nickel system is a simple alloy system, as indicated by its phase diagram. Why is it so simple?