Materials

Question 1

metal such as,——–,———-,———– can be in their pure form and when they are known as Metallic elements?

Answer 1

1.gold
2.sliver
3.copper
4.aluminum

Question 2

when a metal contains a combination of two or more metals,it is then considered an ———?

Answer 2

alloy.

Question 3

expanded metal it can be used ?

Answer 3

for security purposes, saftey guards for moving parts on equipment and machinery.

Question 4

what is commonly used in the sheet metal trade for sound attenuation.

Answer 4

perforated metal.

Question 5

perforated metal the holes can be ?

Answer 5

round , square, hexagonal, oblong, and many others.

Question 6

hardware cloth or bird screen it comes some common sizes is ?

Answer 6

1/4’’ by 1/4
1/2’’ by 1/2’’
1’’ by1’’

Question 7

hardware cloth used for?

Answer 7

extensively to cover openings of hoods and vents prevent the entry of unwanted pests.

Question 8

what is brittleness?

Answer 8

is in a metal is the ability to withstand distortion.

Question 9

materials such as glass, cast, iron, and very hard steel [files] are considered?

Answer 9

brittle.

Question 10

conductivity may refer to either ?

Answer 10

heat conductivity or electrical conductivity.

Question 11

what is an excellent conductor of both heat and electricity and used extensively as a cable in electrical systems?

Answer 11

copper.

Question 12

what is the ability to withstand stretching ,bending orn twisting past ?

Answer 12

ductile.

Question 13

what is elasticity?

Answer 13

the tendency of metal to return to it’s original shape after forces have caused the metal to become deformed.

Question 14

what is the ability to withstand mechanical processing such as rolling , forging and hammering without cracking or braking ?

Answer 14

mealleable

Question 15

what is strength ?

Answer 15

is the amount of high ,steady stress a metal can withstand before it yields.

Question 16

What is toughness?

Answer 16

Is the ability of a metal to withstand an impact load.

Question 17

Example of tough metal?

Answer 17

Titanium.

Question 18

What is the combination of operations involving the heating and cooling of metal?

Answer 18

Heat treatment.

Question 19

Heat treatment falls into three categories?

Answer 19

Annealing
Quenching
Tempering

Question 20

Annealing is

Answer 20

A process used to release internal stresses in hardened metal.

Question 21

What is that cooling of metal that is heated by immersion in a medium such us water and oil ?

Answer 21

Quenching

Question 22

Tempering is ?

Answer 22

The increasing the toughness and decreasing hardness.

Question 23

Practically all the work that is done to metal in shop is ?

Answer 23

Cold work.

Question 24

What is the result of when the metal is exposed to the oxygen in the atmosphere?

Answer 24

Oxidation.

Question 25

Stainless steels have the addition of ?

Answer 25

Chromium.

Question 26

What is a corresive process that results when dissimilar metals come in contact with an electrolyte such as moisture?

Answer 26

Galvanic action.

Question 27

One way to prevent this galvanic action from happening is to provide a barrier between the two metals such barriers include?

Answer 27

Strips of lead between the metal Heavy tinning of the ferrous metal Good quality Heavy coat.

Question 28

Ferrous metal or metal using?

Answer 28

The us standard gauge.

Question 29

Non ferrous also known as the brown sharpe using?

Answer 29

American standard wire gauge.

Question 30

Metals are broken into two basic groups?

Answer 30

Ferrous and Non ferrous.

Question 31

Steel is an alloy primarily composed of iron with a carbon content between——— and———— by weight depending on the grade?

Answer 31

0.02 percent and 1.7 percent.

Question 32

Black iron may?

Answer 32

Either hot rolled or cold rolled.

Question 33

Black iron that measures more than 1/8” is called?

Answer 33

Steel plate.

Question 34

When welding zinc coated sheets, ventilation of the zinc oxide fumes is crucial to prevent an illness known as?

Answer 34

The zinc chills or metal fume fever.

Question 35

Another disadvantage of zinc coated metal is not to used on any food ?

Answer 35

Because the zinc and its compounds are poisonous.

Question 36

What are produced by electroplating zinc onto steel in continuous process?

Answer 36

Electrogalvanizing

Question 37

Steel sheets that have zinc added to them electrogalvanzing go by the trade name of ?

Answer 37

Satincoat Paintlock And Wipecoat.

Question 38

26 gauge sheets of galvanized iron will be thicker than a 26 gauge sheet of black iron? True or false

Answer 38

True

Question 39

Gal alime is zinc aluminum alloy coating with superior corrosion resistance used for?

Answer 39

The outer wall B- vent an L-vent chimney and fittings.

Question 40

One of the most common types of stainless steel used in the sheet metal trade is ?

Answer 40

304 of the basic 18-8 group which contains 18’/‘ chromium, 8 percent nickel,0.08 percent carbon (max) and the rest of steel

Question 41

Stainless steel comes in various finishes?

Answer 41

1 finish - where finish is not important. 2d finish a dull finish. 2B finish plan finish. 4 finish a stain finish on one side used restaurant, kitchen.

Question 42

When working with stainless steel?

Answer 42

All work areas should be iron free to prevent contamination and possible corrosion of the metal.

Question 43

Non ferrous metal consists elements are ?

Answer 43

Copper, and aluminum or alloys such as brass.

Question 44

Aluminum is obtained from an ore called?

Answer 44

Bauxite , which is found mainly the tropics and sub tropics with some deposits in Europe

Question 45

Aluminum is lightweight weighing about ?

Answer 45

One theird the weight of steel.

Question 46

To avoid fracturing,aluminum should be bent using a bend radius of ?

Answer 46

3 times the material thickness.

Question 47

Aluminum has many uses?

Answer 47

Automotive Aerospace and Marine industries.

Question 48

Aluminum is gauged in ?

Answer 48

Decimal parts of an inch or the brown and sharpe gauge.

Question 49

What is reddish brown metal that is considered an element?

Answer 49

Copper

Question 50

What is the advantage of copper?

Answer 50

Excellent conductor of heat and electricity.

Question 51

When copper oxidizes it forms a greenish coating that is called?

Answer 51

Patina

Question 52

Copper is gauged by weight in ?

Answer 52

Ounces per square foot.

Question 53

Brass is?

Answer 53

The common name used for all copper zinc alloys.

Question 54

What is the advantage of brasses?

Answer 54

Are highly malleable and are easily cast ,forged, rolled and pressed.

Question 55

There are two basic categories of plastics?

Answer 55

Thermosetting and Thermoplastic.