Aluminum and Aluminum Welding

Question 1

Which metal is lighter than aluminum?

a) magnesium
b) copper
c) steel
d) manganese

Answer 1

a) magnesium

Question 2

Aluminum is a reactive metal. What is meant by reactive?

Answer 2

A reactive metal is one that readily reacts with other elements. Aluminum reacts very quickly with oxygen to form aluminum oxides.

Question 3

Aluminum has a refractory oxide. What is a refractory oxide?

Answer 3

Refractory oxide means that the oxide is difficult to melt, reduce, or work,. The oxide of aluminum melts at a much higher temperature than the parent metal.

Question 4

How does the electrical and thermal conductivity of aluminum compare with that of mild steel?

Answer 4

the electrical and thermal conductivity of aluminum is approximately 4 times that of mild steel.

Question 5

What is the approximate melting points of the following materials?

a) aluminum
b) aluminum oxide

Answer 5

a) 660 degrees C (1220 degrees F)

b) 2037 degrees C )3700 degrees F)

Question 6

Under the same conditions a section of aluminum would deflect ___ times as much as a similar section of mild steel.

Answer 6

Under the same conditions a section of aluminum would deflect 3 times as much as a similar section of mild steel

Question 7

What process may be used to enhance the aluminum oxide film for increased corrosion resistance?

Answer 7

Anodizing increases the thickness of the oxide layer.

Question 8

The coefficient of linear expansion of aluminum is approximately:

a) equal to that of steel
b) half that of steel
c) twice that of steel
d) four times that of steel

Answer 8

c) twice that of steel

Question 9

In the Aluminum Association wrought aluminum alloy numbering system, the first digit indicates:

a) the alloy group
b) the aluminum alloy
c) the aluminum purity over 99.00%
d) modifications to the original alloy

Answer 9

a)the alloy group

Question 10

In the Aluminum Association wrought aluminum alloy numbering system, the second digit indicates:

a) the alloy group
b) the aluminum alloy
c) the aluminum purity over 99.00%
d) modifications to the original alloy

Answer 10

d) modifications to the original alloy

Question 11

What is the purity of 1050 aluminum alloy?

Answer 11

1050 aluminum alloys are 99.50% pure

Question 12

In the Aluminum Association wrought aluminium alloy number system for 1XXX series, the last 2 digits indicate:

a) the alloy group
b) the aluminum alloy
c) the aluminum purity over 99.00%
d) modifications to the original alloy

Answer 12

c) the aluminum purity over 99.00%

Question 13

What does the number 43 indicate in the filter wire designation of ER4043?

a) the carbon content
b) the alloys added
c) the minimum purity
d) the percentage of magnesium added.

Answer 13

b) the alloys added

Question 14

which aluminum alloy contains substantial amounts of magnesium?

a) AA 1030
b) AA 2014
c) AA 5356
d) AA 4043

Answer 14

c) AA 5356

Question 15

What does the fourth digit indicate for an aluminum alloy casting?

a) minimum aluminum content
b) product form
c) modifications of the original alloy
d) types of heat treatment

Answer 15

b) product form

Question 16

The aluminum wrought alloys in the groups 1XXX, 3XXX and 5XXX series are:

a) heat-treatable
b) non-heat treatable
c) hardenable
d) temperable

Answer 16

b) non-heat treatable

Question 17

The aluminum wrought alloys in the groups 2xxx, 6xxxx and 7xxx series are:

a) heat-treatable
b) non-heat treatable
c) unworkable
d) unused.

Answer 17

a) heat-treatable

Question 18

How can the mechanical properties of heat-treated aluminum alloys be restored after welding?

Answer 18

The properties can be restored by heat-treating again.

Question 19

Heating an aluminum alloy to a temperature below its melting point for a specified period of time and then quenching from this temperature is called:

a) tempering
b) hardening
c) aging
d) solution heat-treating.

Answer 19

d) solution heat-treating.

Question 20

Non-heat treatable wrought alloys are designated with several levels of mechanical properties. Which does not indicate a mechanical property designation?

a) H1 (work hardened only)
b) A (anodized)
c) O (fully annealed)
d) F (as fabricated)

Answer 20

b)A (anodized)

Question 21

The mechanical properties of ____ aluminum alloys are improved by cold working and drawing.

Answer 21

The mechanical properties of non-heat treatable aluminum alloys are improved by cold working and drawing

Question 22

Which two filler metals may be used to weld most weldable aluminum alloys?

a) ER1100 and ER3003
b) ER4043 and ER5356
c) ER5083 and ER5454
d) ER6061 and ER6351

Answer 22

b) ER4043 and ER5356

Question 23

When welding a 6061-T6 alloy, which metal alloy is generally the best choice?

Answer 23

ER4043

Question 24

What is the primary consideration when selecting a filler metal when using GMAW on aluminum ?

a) the amperage and voltage settings
b) matching base metal and filler metal chemistry and mechanical properties
c) the temper designation of the base metal
d) the type of joint to be welded

Answer 24

b) matching base metal and filler metal

Question 25

What is the true of an ER5356 aluminum alloy? a) there have been no modifications b) it is 99.56% pure aluminum c) it is heat-treatable aluminum d) Magnesium is the major alloying element

Answer 25

d) Magnesium is the major alloying element

Question 26

What type of alloy is an ER4043 filler wire? a) aluminum and silicon b) aluminum and magnesium c) aluminum and manganese d) silicon and manganese

Answer 26

a)aluminum and silicon

Question 27

Where are the drive rolls located on a pull type drive system? a) in the gun itself, close to the contact tip b) in the main wire feed unit c) on the drum some distance behind the wire feeder d) the same place as on a push type system

Answer 27

a) in the gun itself, close to the contact tip

Question 28

A pull type welding gun is designed to be used with a) hard wires b) soft wires c) solid core wires d) tubular wires

Answer 28

b) soft wires

Question 29

What type of wire drive system allows greater machine-to-work distances? a) push system b) push-pull system c) soft wires are taken through long liners d) hard wires are taken through long liners

Answer 29

b) push-pull system

Question 30

push-pull guns are an advantage when: a) soft wires are taken through short liners b) hard wires are taken through short winers c) soft wires are taken through long liners d) hard wires are taken through long liners

Answer 30

c) soft wires are taken through long liners

Question 31

What type of metal transfer occurs with aluminum GMAW and 100% argon shielding? a) short circuiting b) globular c) dip transfer d) spray

Answer 31

d) spray

Question 32

What is the most likely cause of porous, dirty, weld bead? a) drag technique. b) push technique c) brushing the aluminum with a stainless steel brush d) spray transfer mode

Answer 32

a) drag technique.

Question 33

What is the likely cause of the wire melting back on the contact tip? a) wire feed speed too high b) wire feed speed too low c) welding with a forehand technique d) diameter of the wire matches the drive rolls

Answer 33

b) wire feed speed too low