Material Process Exam 2
Which of the following are alternative names for indirect extrusion (two correct answers):
(a)backward extrusion, (e) reverseextrusion
Which of the following most closely typifies the sintering temperatures in PM: ( Tm = melting temperature of the metal)
0.8 Tm
Which of the following will improve surface finish in grinding (three best answers):
denser wheel structure lower workspeed higher wheel speed
The average flow stress is the flow stress multiplied by which of the following factors?
1/(1+n)
In precipitation hardening, the hardening and strengthening of the metal occurs in which one of the following steps:
aging
Which one of the following abrasive materials is most appropriate for grinding steel and cast iron
aluminum oxide
Which one of the following surface-hardening treatments is the most common:
carburizing
Which of the following casting processes are permanent mold operations (three correct answers):
centrifugal casting die casting slush casting
Which of the following are classified as forging operations
coining, fullering, swagging, upsetting
Most sheet metalworking operations are performed as which one of the following
cold working
The upper half of a sand-casting mold is called which of the following:
cope
Which of the following casting processes are expendable mold operations
investment casting sand casting shell molding
Which of the following are advantages and characteristics of hot working relative to cold working
isotropic mechanical properties fracutre of workpart is less likely lower deformation forces More significant shape changes are possible
Turbulence during pouring of the molten metal is undesirable for which of the following reasons
it increases erosion of the mold surfaces it increases the formation of metallic oxides that can become entrapped during solidification
Which one of the following is the best definition of bend allowance:
length before bending of the straight sheet-metal section to be bent
investment casting is also known by which one of the following names:
lost wax process
A misrun is which one of the following defects in casting:
metal solidifies before fillig the cavity
which one of the following conventional machining processes is closest to grinding
milling
Which of the following design features would be difficult or impossible to achieve by conventional pressing and sintering
outside rouned corners threaded holes vertical wall thickness of 1/8mm (3mm)
Which one of the following stamping dies is the most complicated:
progressive die
mpregnation refers to which of the following (two best answers):
putting polymers into the pores of a PM part Soaking oil by capillary action into the pores of a PM part
Which of the following bulk deformation processes are involved in the production of nails (both nail head and nail body) for lumber construction
rolling bar and wire drawing upset forging
Which of the following are bulk deformation processes
rolling, forging, extrusion
Which one of the following casting processes is the most widely used:
sand casting
The cutting force in a sheet-metal blanking operation depends on which mechanical property of the metal:
shear strength
A riser in casting is described by which of the following (three correct answers)
source of molten metal to feed the casting and compensate for shrinkage during solidification waste metal that is usually recycled metal tht is not part of the casting
On which one of the following metals is the treatment called austenitizing be performed:
steel
Which one of the following abrasive processes achieves the best surface finish: a.centerless
super finishing
The treatment in which the brittleness of martensite is reduced is called which one of the following:
tempering
Total solidification time is defined as which one of the following:
time between pouring and complete solidification
In a sheet-metal-cutting operation used to produce a flat part with a hole in the center, the scrap piece that was cut out to make the hole is called a slug.
true
Which of the following metals would typically be used in die casting
zinc, tin aluminum
Which of the following rolling mill types are associated with relatively small diameter rolls in contact with the work
(a) cluster mill, (c)four-high mill
Which of the following are the usual objectives of heat treatment (three best answers):
(a) increase hardness (d) reduce brittleness (f) relieve stresses
