Chapter 22 CUTTING TOOL TECHNOLOGY
22.4 Of the following cutting conditions, which one has the greatest effect on tool wear: (a) cutting speed, (b) depth of cut, or (c) feed?
a
22.9 Which of the following is not a common ingredient in cemented carbide cutting tools (two correct answers): (a) Al2O3, (b) Co, (c) CrC, (d) TiC, and (e) WC?
a and c
22.12 If you had to select a cemented carbide for an application involving finish turning of steel, which C grade would you select (one best answer): (a) C1, (b) C3, (c) C5, or (d) C7?
d
22.2 Which of the following are the two main types of gradual wear on a cutting tool: (a) clearance wear, (b) crater wear, (c) flank wear, (d) nose wear, and (e) notch wear?
Answer. (b) and (c). Answers (d) and (e) are special cases of (c). Answer (a) is a red herring.
22.15 Most ceramic cutting tools are fabricated from which one of the following materials: (a) aluminum oxide, (b) cubic boron nitride, (c) titanium carbide, (d) titanium nitride, or (e) tungsten carbide?
a
22.18 Chip breakers are frequently used with single-point tools. They work by forcing the chips to curl more tightly than they would naturally be inclined to curl, thus causing them to fracture: (a) true or (b) false?
a
22.13 Which of the following processes are used to provide very thin coatings on the surface of coated carbide inserts (two best answers): (a) chemical vapor deposition, (b) electroplating, (c) physical vapor deposition, (d) pressing and sintering, and (e) spray painting?
a and c
22.10 An increase in cobalt content has which of the following effects on WC Co cemented carbides (two best answers): (a) decreases hardness, (b) decreases transverse rupture strength, (c) increases hardness, (d) increases toughness, and (e) increases wear resistance?
a and d
22.6 As an alloying ingredient in high-speed steel, tungsten serves which of the following functions (two best answers): (a) depth hardenability during heat treatment, (b) forms hard carbides to resist abrasion, (c) improves strength and hardness, (d) increases corrosion resistance, (e) increases hot hardness, and (f) increases toughness?
b and e
22.8 Cast cobalt alloys typically contain which of the following as their main ingredients (three best answers): (a) aluminum, (b) cobalt, (c) chromium, (d) iron, (e) nickel, (f) steel, and (g) tungsten?
b c and g
22.16 Sialon is a cutting tool material containing which of the following as its principal ingredients (two correct answers): (a) aluminum oxide, (b) cubic boron nitride, (c) silicon carbide, (d) silicon nitride, (e) titanium nitride, and (e) tungsten carbide?
a and d
22.1 Of the three possible modes by which a cutting tool can fail during a machining operation, which one is most preferable: (a) fracture failure, (b) gradual wear, or (c) temperature failure?
b
22.14 Which one of the following materials has the highest hardness: (a) aluminum oxide, (b) cubic boron nitride, (c) high-speed steel, (d) titanium carbide, or (e) tungsten carbide? Answer. (b).
b
22.19 Which of the following drill types would be the most likely choice to drill a hole with a 100 mm (4.0 in) diameter (one best answer): (a) gun drill, (b) spade drill, (c) straight-flute drill, (d) twist drill?
b
22.5 Which of the following are the three most important properties of a tool material that are suggested by the three modes of tool failure: (a) ductility, (b) hot hardness, (c) impact resistance, (d) tensile strength, (e) toughness, and (f) wear resistance?
b e and f
22.17 How many elements of tool geometry are required to completely specify a single-point tool (one correct answer): (a) two, (b) five, (c) seven, (d) eight, or (e) ten?
c
22.20 Which of the following are the two main functions of a cutting fluid in machining (two best answers): (a) improve surface finish on the workpiece, (b) reduce forces and power, (c) reduce friction at the tool chip interface, (d) remove heat from the process, and (e) wash away chips?
c and d
22.11 Steel-cutting grades of cemented carbide are typically characterized by which of the following ingredients (three correct answers): (a) Co, (b) CrC, (c) Mo, (d) Ni, (e) TiC, and (f) WC?
a e and f
22.3 The basic Taylor tool life equation defines the relationship between which two of the following variables: (a) cutting speed, (b) depth of cut, (c) feed, (d) feed rate, (e) tool life, and (f) work material hardness?
a and e
22.7 As an alloying ingredient in high-speed steel, chromium serves which of the following functions (three best answers): (a) depth hardenability during heat treatment, (b) forms hard carbides to resist abrasion, (c) improves strength and hardness, (d) increases corrosion resistance, (e) increases hot hardness, and (f) increases toughness?
a b anmd d