ME 381 Manufacturing HW5-7
Microsystem technology includes which of the following (three best answers): (a) LIGA technology, (b) microelectromechanical systems, (c) micromachines, (d) nanotechnology, (e) and precision engineering?
(a), (b), and (c).
Which one of the following is closest to the temperatures used in plasma arc cutting?
11,000°C (20,000°F)
Which one of the following materials is closest to diamond in hardness: aluminum oxide carbon dioxide cubic boron nitride silicon dioxide tungsten carbide
cubic boron nitride
Which one of the following is the most common element in the earth's crust: calcium iron oxygen aluminum silicon
oxygen
Etch factor is which of the following in chemical machining (more than one)? A = degree of anisotropy, C = specific removal rate, d = depth of cut, I = current, t = time, and u = undercut.
A d/u
Which of the following metals are used as the matrix material in fiber-reinforced MMCs (two best answers): Aluminum Iron Copper Zinc Magnesium
Aluminum Magnesium
Which of the following materials are used as fibers in fiber-reinforced plastics (four best answers): Cast Iron Aluminum oxide Epoxy Polyester Silicon Kevlar 49 E-glass Boron
Aluminum oxide Kevlar 49 E-glass Boron
Which of the following terms describes what a cemented carbide is (one best answer): Ceramic Cermet Composite Metal New ceramic Traditional ceramic
Cermet
Which of the following metals are used as the matrix metals in nearly all WC cemented carbides and TiC cermets (two correct answers): Lead Tungsten Cobalt Chromium Tungsten carbide Aluminum Nickel
Cobalt and Nickel
Which of the following processes would be appropriate to drill a hole with a square cross-section, 0.25 inch on a side and 1-inch deep in a steel workpiece (one best answer)?
EDM
Applications of electron beam machining are limited to metallic work materials due to the need for the work to be electrically conductive: T or F
F
Glass ceramics are polycrystalline ceramic structures that have been transformed into the glassy state: T or F
F
True or False: The reinforcing phase is the matrix within which the secondary phase is imbedded
F
Which one of the following reinforcing geometries offers the greatest potential for strength and stiffness improvement in the resulting composite material? Particles Fibres Flakes Infiltrated phase
Fibres
For a given weight of metallic powders, which of the following factors effect an increase in surface area? (two best answers): Higher shape factor Smaller particle size Large particle size Smaller shape factor
Higher shape factor Smaller particle size
Which of the following processes would be appropriate for cutting a hole of 0.003 inch diameter through a plate of aluminum that is 1/16-inch thick (one best answer)?
Laser beam machining
Wood is which one of the following composite types? CMC MMC PMC
PMC
Of the following processes, which one is noted for the highest material removal rates?
Plasma arc cutting
Identify which of the following materials are not composites (two correct answers): Wood Plywood Phenolic molding compound Cemented carbide Rubber in automobile tires Portland cement 1020 steel
Portland cement 1020 steel
Properties and characteristics of the glass-ceramics include which of the following (two best answers): Strong, relative to other ceramics High thermal expansion Efficiency in processing Electrical conductor
Strong, relative to other ceramics Efficiency in processing
Self-assembly is likely to be the most important of the nanofabrication processes because of its low cost, its capacity for producing structures over a range of sizes (from nanoscale to macroscale), and its general applicability to a wide variety of products. T or F
T
T or F: Ultrasonic machining can be used to machine both metallic and nonmetallic materials
T
Dip-pen nanolithography uses which one of the following techniques and/or devices: (a) atomic force microscope, (b) chemical vapor deposition, (c) electron beam lithography, (d) nano-imprint lithography, or (e) self-assembly?
a
Which of the following forms of radiation have wavelengths shorter than the wavelength of ultraviolet light used in photolithography (two correct answers): (a) electron beam radiation, (b) natural light, and (c) X-ray radiation?
a and c
Which of the following processes use mechanical energy as the principal energy source (may be more than one)? Grinding Milling Ultrasonic machining Water jet cutting
all of them
The aspect ratio in microsystem technology is best defined by which one of the following: (a) degree of anisotropy in etched features, (b) height-to-width ratio of the fabricated features, (c) height-to-width ratio of the MST device, (d) length-to-width ratio of the fabricated features, or (e) thickness-to-length ratio of the MST device?
b
Which of the following are considered techniques that fall within the category called top-down approaches to nanofabrication (three best answers): (a) biological evolution, (b) electron-beam lithography, (c) micro-imprint lithography, (d) scanning probe techniques, (e) self-assembly, and (f) X-ray lithography?
b, c, f
A self-assembled monolayer has a thickness that is which one of the following: (a) one micrometer, (b) one millimeter, (c) one molecule, or (d) one nanometer?
c
Which of the following are considered techniques that fall within the category called bottom-up approaches to nanofabrication (three best answers): (a) electron beam lithography, (b) extreme ultraviolet lithography, (c) chemical vapor deposition to produce carbon nanotubes, (d) nanoimprint lithography, (e) scanning probe techniques, (f) self-assembly, and (g) X-ray lithography?
c, e, f
Which of the following contains significant amounts of aluminum oxide (three correct answers): Kaolinite Silica Sandstone Quartz Feldspar Corundum Alumina Bauxite
corundum, alumina, bauxite
In the LIGA process, the letters LIGA stand for which one of the following: (a) let it go already, (b) little grinding apparatus, (c) lithographic applications, (d) lithography, electrodeposition, and plastic molding, or (e) lithography, grinding, and alteration?
d
The polymer used to make compact discs (CDs) and digital versatile discs (DVDs) is which one of the following: (a) amino resin, (b) epoxy resin, (c) polyamides, (d) polycarbonate, (e) polyethylene, or (f) polypropylene?
d
The most common work material used in microsystem technology is which one of the following: (a) boron, (b) gold, (c) nickel, (d) potassium hydroxide, or (e) silicon?
e
The three steps in correct order for sintering cycle in powder processing are [A], [B] and [C]
heat, sinter, and cool
Which of the following processes would be appropriate for cutting a narrow slot, less than 0.015 inch wide, in a 3/8- inch thick sheet of fiber-reinforced plastic (more than one)?
laser beam machining water jet cutting
Anisotropic means which one of the following: strength and other properties are a function of curing temperature composite materials with composition consisting of more than two materials properties vary depending on the direction in which they are measured properties are the same in every direction
properties vary depending on the direction in which they are measured
Chemical milling is used in which of the following (may be more than one)?
removing material to make shallow pockets in metal removing metal from aircraft wing panels
Glass products are based primarily on which one of the following minerals: Alumina Corundum Feldspar Kaolinite Silica
silica
Which of the following polymer types are most commonly used in polymer matrix composites: Elastomer Thermoplastics Thermosets
thermosets
Ceramic matrix composites are designed to overcome which of the following weaknesses of ceramics (two best answers): Hardness Hot hardness Toughness Modulus of elasticity Compressive Strength Tensile strength
toughness and tensile strength
Which one of the following terms refers to the glassy state of a material? Devitrified Vitreous Vitiated Crystalline Polycrystalline
vitreous