imse exam 2

The top rotation speed of dental drill rotates around __________ RPM. By comparison, a DeWalt drill has a top speed of __________RPM. 250,000; 2,500 2,500; 250,000

250,000; 2,500

In a turning operation (straight cylindrical turning), if the initial diameter minus the final diameter equals 8 mm, what is the depth of cut? 1 mm 2 mm 4 mm 8 mm

4 mm

Which one of the following plastic codes indicates the safest water bottle reusable for refilling cold water? 1 PET 3 PVC 5 PP 7 PC

5 PP

If you box some leftover dinner for lunch at school and want to reheat in a microwave, a plastic container with which recycling code is the best to use? 1 PET. 4 LDPE. 5 PP. 6 PS.

5PP

See the figure in Question 7, in which case the newly-generated milled surface is smoother (assume all the other process parameters are the same)? A B Impossible to tell

A

According to the different cutting tool wear and failure modes mentioned in the SME video, please match the worn or failed tools in the picture with their wear and failure modes:

A Crate wear B Edge chipping C Notching

In end milling, machined-surfaces can be generated by up milling or down milling as well. Which one is which in this illustration (this illustrates as a top view: looking down at the cutting interface from the top of the rotating tool axis)?

A Down milling B Up milling

In slab milling, machined-surfaces can be generated by up milling or down milling. Which one is which in this illustration?

A Down milling B Up milling

Please match the milling operation illustrated in this figure:

A Down milling B Up milling

Grain size, bond type, and pore size all affect grinding wheel performance. Which one of the following is NOT true? A grinding wheel labeled with a larger grain size number produces rougher surface finish Vitrified bond system is more rigid and more brittle than resin bond system Pore space determines if the wheel has an "open" structure or "closed" structure

A grinding wheel labeled with a larger grain size number produces rougher surface finish

Which type of plastic makes most of today's Lego bricks? PET. PP. PVC. ABS.

ABS

Which one nontraditional machining process is safer for the operators and the environment compared with the other? Abrasive Jet Machining Abrasive Water Jet Machining

Abrasive Water Jet Machining

Please identify the functions of the key components in an ultrasonic machining system: Booster and horn convert(s) low-frequency electrical signal into ultrasonic-frequency electrical signal. Power supply transfuce(s) electrical signal into mechnical vibration. Converter transmit(s) and enlarge the amplitude of mechanical vibration at ultrasonic-frequency

Answer 1:Power supply Answer 2:Converter Answer 3:Booster and horn

See the figure in Question 8, in which case the chip is thin at the beginning and thick at the end? A B

B

According to the orthogonal cutting model assumptions, please select all that are not orthogonal cutting (assume all the cutting edges in the pictures are perfectly sharp). A B C D E F

B, C,D, F

Questions 7-10 are based on the dentist's drill. The anatomical crowns of teeth are covered by dental enamel, which is the hardest tissue in the body. Please rank the following four materials in the order of highest hardness to the lowest: (A. dental enamel; B: gold; C: tungsten carbide; D: mild steel). C>D>A>B C>A>D>B A>C>D>B

C>A>D>B

Superabrasives include CBN (cubic boron nitride) and diamond. __________ grinding wheels are used to grind ferrous metals; while __________ grinding wheels are used to grind non-ferrous metals and non-metals. CBN; diamond Diamond; CBN

CBN; diamond

Which one of the following is NOT an element commonly found in plastics? Carbon. Hydrogen. Oxygen. Calcium

Calcium

Which of the following is NOT a limitation of abrasive jet machining (AJM)? Material removal rate is relatively low. Surface finish is not good when processing some ductile materials. Cannot be applied to machining brittle materials. Fine abrasive particles can be a health hazard to machine operators and the environment.

Cannot be applied to machining brittle materials.

Which tool material has the best hot hardness performance among the following? Mild carbon steel Carbon tool steel High-speed steel Carbide

Carbide

What are the typical processes in sequence to machine a high-accuracy hole (assume all processes are necessary)? Centering and countersinking—reaming—drilling—boring Centering and countersinking—drilling—boring—reaming Centering and countersinking—boring—drilling—reaming

Centering and countersinking—drilling—boring—reaming

The light airplane body is primarily made of what material? (Pick only one) Metals and alloys. Plastics. Ceramics. Composites.

Composites.

Please identify what types of tool wear would happen at the following two blank places. The upper is _______wear and the lower blank is_______wear. crater, flank flank, crater

Crater, flank

Cubic boron nitride (CBN) and polycrystalline diamond (PCD) are two superabrasives. __________ is used for machining ferrous materials, and __________ is used for machining non-ferrous materials. Cubic boron nitride (CBN); Polycrystalline diamond (PCD) Polycrystalline diamond (PCD); Cubic boron nitride (CBN)

Cubic boron nitride (CBN); Polycrystalline diamond (PCD)

It is found that the problem as described in Question 8 can be solved or improved by changing the depth of cut. Should the depth of cut be increased or decreased to reduce the deflection? Increased Decreased

Decreased

Which one of the following orders represents the surface roughness (from the roughest to the smoothest) generated by these processes? Honing > Reaming > Drilling. Reaming > Drilling > Honing. Drilling > Reaming > Honing. Drilling > Honing > Reaming.

Drilling > Reaming > Honing.

Please judge the following statement: drilling operation can only be conducted on a drill press. True. False.

False

Please judge the following statement: in a machining process (including both conventional and nontraditional), the hardness of the cutting tool must always be higher than that of the workpiece. True. False.

False

See the figure below, cutters for slab milling may have straight or helical teeth. Which one results in oblique (when a cutting edge is angled to the direction of motion of the workpiece) cutting action? Straight teeth Helical teeth

Helical Teeth

What are the properties that an ideal cutting tool should have (please select all)? High hardness and sufficient hot hardness High toughness to resist impact Can be easily resharpened Chemically stable

High hardness and sufficient hot hardness High toughness to resist impact Chemically stable

Where is the shear angle (φ) in this figure bellow? I II III

I

Which is the clearance angle? I II III IV

I

Which is the tool (wedge) angle? I II III IV

III

Questions 1-6 are based on the biopsy process. A biopsy is the removal of tissue from any part of the body to examine it for disease. Most of them remove a small tissue sample with a needle (Fig. B). Tissue cutting by a needle is greatly influenced by the geometry of its cutting edges. The orthogonal cutting is employed to model this process (Fig. A). Please identify the following tool geometry: Choose from Angles I to IV. Which is the rake angle? I II III IV

IV

How would you recommend some adjustments to improve the surface finish in Question 8? (Choose all answers that will help) Increase cutting speed Decrease cutting speed Increase feedrate Decrease feedrate Choose a tool has a smaller nose radius Choose a tool has a larger nose radius

Increase cutting speed Decrease feedrate Choose a tool has a larger nose radius

It is found that the "boring bar deflection" problem can be solved or improved by changing the rake angle of the boring tool. Should the rake angle be increased or decreased to reduce the deflection so the exit diameter P2 can be the same as the entrance diameter P1? Increased. Decreased.

Increased

It is found that the problem as described in Question 8 can be solved or improved by changing the rake angle of the cutting tool. Should the rake angle be increased or decreased to reduce the deflection? Increased Decreased

Increased

See the microscopic image on the right, in the middle is a steel turning chip side view; please tell which side is generated closely along the rake face on the cutting tool? Upper (rough). Lower (smooth)

Lower (Smooth)

The dental drill show in Questions 7 has diamond abrasive particles bonded on the tool surface. What type of bonding is used? Vitrified bond Resin bond Metal bond

Metal bond

Which one of the following is not considered as a single-point machining process? Turning. Boring. Facing. Milling.

Milling.

For a batch of parts, the bored hole should have the same diameter all way through according to the drawing. When the boring operation was finished, it was found that the hole diameter at position P2 was always smaller than that at P1 for all the parts in this batch. The cause was found to be the deflection of the baring bar. (Assume the baring bar is made of steel.) Can the problem be solved or improved by heat treatment of the baring bar (so the steel will have higher yield strength)? Yes No

No

Which type of plastic is not derived from petroleum? PLA. PP. PVC. ABS.

PLA.

Pressing down the piezo ignition button to fire up the lighter is the application of __________. Inverse Piezoelectric Effect Piezoelectric Effect

Piezoelectric Effect

According to the video "cool chips", when the cutting fluid is applied into cutting zone, many things will happen. Which one of the following will NOT happen? The shear angle increases. Cutting temperature decreases. Built-up edge (BUE) disappears. Power consumption increases.

Power consumption increases.

According to the chart "Tool materials over time", (what factor) _________ is the main driving force to the development of new cutting tool materials? Productivity Hardness and toughness Life span Cost

Productivity

In "How is made" grinding wheels, what bonding material is used? Vitrified bond Resin bond Metal bond

Resin bond

In which EDM process, tool wear is a more concerning issue? Sinker EDM Wire EDM

Sinker EDM

Some biopsy uses a core needle as shown in Fig. C in Question 1, it is a critical one-time use surgical tool under extremely hygienic conditions. What is the tool material you recommend? Plain carbon steel Aluminum alloy T10 tool steel Stainless steel Tungsten carbide

Stainless steel

A turning machine (lathe) is a very versatile tool, please select all operation processes that can be done on a lathe (suppose you have the correct cutting tools). Straight and Taper Turning Contour Turning or Profiling Forming (material removal) Chamfering Lapping Thread chasing Slab milling Holemaking (Drilling and Boring) Facing Grooving and parting

Straight and Taper Turning Contour Turning or Profiling Forming (material removal) Chamfering Thread chasing Holemaking (Drilling and Boring) Facing Grooving and parting

This is a typical surface profile generated by a turning operation. Note: one of the left is a high magnification microscopic image not thread chasing. What is a reasonable explanation of these equally-spaced grooves? Machine tool chatter due to vibration The workpiece has a very rough surface. The combination of the motions of tool linear feed and workpiece rotation. The hot hardness of the tool is not sufficient to satisfy this operation,

The combination of the motions of tool linear feed and workpiece rotation.

Which one of the following is not one of the assumptions of this cutting model? The cutting tool is perfectly sharp. The uncut chip thickness is constant. The rake angle is always positive. There are no segmented chips generated.

The rake angle is always positive.

In drilling with a conventional twist drill, ___________ is helping to remove the cutting chips from the drilling hole? The infeed of the rotating lips The infeed of the rotating web The screw action of the rotating helical flutes The upward exiting rubbing against the walls of the hole

The screw action of the rotating helical flutes

EDM has several benefits. Which one of the following is NOT among these benefits? No cutting forces (due to no contact). Burr-free edges. Intricate (complex) details can be cut. The tool never wears.

The tool never wears.

Plastic cups are made from ________ Thermosets. Thermoplastics.

Thermoplastics.

Which plastic materials are easier to recycle and use? Thermosets. Thermoplastics.

Thermoplastics.

Which plastic materials are stronger and more rigid than the other? Thermosets. Thermoplastics.

Thermosets.

In turning, if DOC, RPM, and f are kept constant and there is no vibration issue on the machine system, to obtain a better surface which tool should be selected? Tool A Tool B It does not depend on the tool selection.

Tool A

In this turning operation (a metal lathe turning a doorknob with mirrorlike surface finish), which one of the two tools is recommended? Tool A Tool B

Tool B

In Ultrasonic Machining (USM), an abrasive slurry is used while in Rotary Ultrasonic Machining (RUM) a fix-abrasive tool (diamond grit-bonded core drill) is used. True. False

True

Some voids/cavities are beneficial to grinding wheel operation as they can provide space for coolant retention and chip clearance. True False

True

With other process parameters kept the same, the greater the depth of cut, the greater the cutting forces. True False

True

Both Ultrasonic Machining (USM) and Rotary Ultrasonic Machining (RUM) are mechanical nontraditional machining processes (material removal is realized by mechanical impacts). True. False

True.

What is the tool material you recommend as the tool material for the right figure in Question 7 (the drill tip part)? Plain carbon steel Aluminum alloy T10 tool steel Stainless steel Tungsten carbide

Tungsten carbide

Which one of the following material is suitable to be made into an abrasive jet machining (AJM) nozzle? Low carbon steel High speed steel (HSS) Tungsten carbide (WC) Stainless steel

Tungsten carbide (WC)

How does the production line dry the ink printed on cups? UV-lamp cold-air heating

UV-lamp

Refer to the Figures (A and B) below. In the turning process, which one has a higher cutting speed? Workpiece has a larger diameter. Workpiece has a smaller diameter The above two have the same cutting speed since the RPMs are identical.

Workpiece has a larger diameter.

What are the two major components of a grinding wheel? They are _______ material and ______ material.

abrasive and bonding

The instrument panels (made of metal) in the light aircraft video are cut by __________ process? twist drilling CNC milling laser cutting abrasive water jet machining abrasive jet machining

abrasive water jet machining

Up milling and down milling happen during ___________. slab milling only face milling only end milling only all the three milling operations only in face milling and end milling

all the three milling operations

Between the two common abrasive materials (aluminum oxide and silicon carbide), __________ is primarily used to grind ferrous materials, and __________ is a go-to option for non-ferrous metal grinding. aluminum oxide; silicon carbide. silicon carbide; aluminum oxide they are interchangeable

aluminum oxide; silicon carbide.

In a sinker EDM, the workpiece is usually the __________ while the tool is often used as the __________. cathode; anode anode; cathode depends on the hardness of the two materials

anode; cathode

In general, the surface roughness and accuracy produced by grinding is generally ________ that produced by turning or milling. approximately 10 times better than worse than about the same as

approximately 10 times better than

The failure type in the material removal mechanisms for sinker ultrasonic machining (USM) is mainly __________. ductile failure removal brittle failure removal

brittle failure removal

The two most commonly-used tool materials for sinker EDM are ____ and ____.

copper, graphite

Abrasive machining mechanism is a combination of ___________ , ___________, and __________. cutting cracking etching plowing shredding rubbing oxidizing

cutting, plowing, rubbing

As shear angle φ increases, the chip thickness ________. increases. decreases. not correlated.

decreases

When the uncut chip thickness remains unchanged, as the shear angle increases, the chip thickness __________ . increases decreases

decreases

Pockets such as those in this figure are usually machined by __________ milling. slab face end

end

In a milling operation, if the newly-machined surface is generated perpendicular to the cutter rotation axis, it can be __________ milling. slab face either slab or face

face

The shear angle is of fundamental importance. For any given uncut chip thickness, a small shear angle means a ______ cutting force. higher lower

higher

Generally speaking, a decrease in cutting speed will ________ the tool life (assume other process parameters stay unchanged). increase decrease not affect

increase

When machining very hard materials such as hardened steels or brittle materials such as ceramics and semiconductor materials, abrasive machining __________ preferable to turning and milling. is is not

is

The light aircraft video shows the manufacturing of airplanes. In making these airplanes, the processes are ______. labor-intensive highly-automated

labor-intensive

Before the procedure, the patient will receive a type of anesthesia (Anesthesia is medication to block the awareness of pain). In order to reduce the pain as much as possible, a biopsy needle has a __________ rake angle large positive large negative zero

large positive

Generally speaking, the _______ the rake angle, the sharper the cutting tool is, thus cuts easier. larger smaller

larger

In a boring operation (to enlarge an existing hole as shown in this figure), if the tooltip is set lower than the rotation axis of the workpiece, the effective rake angle will be __________than that when the tooltip is set at the same height as the rotation axis of the workpiece. smaller larger

larger

In a turning operation, if the tool tip is set higher than the rotation axis of the workpiece, the effective rake angle will be __________ than that when the same tool tip is set at the same height as the rotation axis of the workpiece; and the effective clearance angle will be __________ than that when the same tool tip is set at the same height as the rotation axis of the workpiece. smaller; larger larger; smaller larger; unchanged smaller; unchanged

larger; smaller

The shear angle is of fundamental importance in chip formation. For any given uncut chip thickness in the orthogonal cutting model, a large shear angle means a __________ cutting force. high low

low

In drilling operation with a standard twist drill, the cutting speed is different along the cutting lips and the chisel edge. Usually, the cutting speed towards the drill center is ________ than that at the outer diameter of the drill. lower higher the same as

lower

The material removal process in abrasive water jet machining (AWJM) is a __________ action? mechanical electrochemical electrothermal chemical

mechanical

To make those plastic ware, at the very beginning, the resin is usually in the form of ______ pellets. liquid. sheets.

pellets.

Casting, forging, and rolling are material processing methods mainly used at the stage of __________ manufacturing. primary secondary

primary

In the video showing the manufacturing process of the milling tools, what is the quenching media used to harden tool workpieces? melten salt salt bath of various temperatures water induction heat

salt bath of various temperatures

In __________ milling, the newly-machined surface is generated by teeth located only on the periphery of the milling cutter. slab face end both slab and face both face and end

slab

For the same situation as described in Question 6, assuming all other process parameters are kept the same, the cutting force (when the tooltip is set lower than the rotation axis of the workpiece) will be __________ than that when the tooltip is set at the same height as the rotation axis of the workpiece. smaller larger

smaller

Plastic casting processes can be used to produce parts from ________ all plastics. thermoplastics only. thermosets only. some thermoplastics and some thermosets.

some thermoplastics and some thermosets.

Most cutting processes are __________ three-dimensional. orthogonal cutting.

three-dimensional.

Please judge the following statement: in conventional machining processes, material removal is always achieved by the generation of cutting chips. True. False

true