AWS Certified Welder Aluminum D1.2 Exam
With Correct Answers (Verified Answers) Plus
Rationales 2026 Q&A | Instant Download Pdf
1. Which aluminum alloy series is most commonly used for welding
in structural applications?
a) 1XXX
b) 2XXX
c) 5XXX
d) 7XXX
The 5XXX series contains magnesium, providing good corrosion
resistance and weldability, making it ideal for structural welding.
2. What is the primary concern when welding aluminum compared
to steel?
a) Higher melting point
b) Oxide layer formation
c) Rapid heat conduction
d) Lower ductility
Aluminum conducts heat quickly, making it difficult to maintain
proper weld pool control.
3. What gas is typically used for GTAW (TIG) welding of aluminum?
a) Oxygen
b) Carbon dioxide
c) Argon-Helium mix
d) Argon
, Argon provides an inert shielding atmosphere to prevent oxidation
during aluminum welding.
4. Which cleaning method is recommended before welding
aluminum?
a) Grinding with steel brush
b) Solvent degreasing only
c) Mechanical cleaning with stainless steel brush
d) Acid etching only
Aluminum forms a refractory oxide layer that must be removed
mechanically before welding.
5. What is a characteristic of 5356 filler metal?
a) Poor corrosion resistance
b) High strength and corrosion resistance
c) Only suitable for brazing
d) Low melting point
5356 is widely used for aluminum structural welding due to its
strength and corrosion resistance.
6. Preheating aluminum prior to welding is typically:
a) Required for all alloys
b) Never required
c) Used for thick sections to reduce cracking
d) Used only for 1XXX series
Preheating helps reduce thermal gradients in thick aluminum
sections, minimizing hot cracking.
7. What is the typical thickness range for fillet welds in aluminum
structures?
a) 1/16” to 1/8”
, b) 1/8” to 1/2”
c) 1/2” to 1”
d) Over 1”
Fillet weld size depends on the thickness of members; 1/8” to 1/2”
is standard for structural aluminum.
8. When using GTAW on aluminum, what is the recommended
polarity?
a) DCEN (Direct Current Electrode Negative)
b) ACEN
c) AC (Alternating Current)
d) DCEP (Direct Current Electrode Positive)
AC allows cleaning action and good penetration, which is essential
for aluminum TIG welding.
9. Which defect is common in aluminum welds due to
contamination?
a) Underfill
b) Porosity
c) Burn-through
d) Overlap
Contamination from oils, moisture, or oxide layers traps gas in the
weld, causing porosity.
10. Why is back-step welding technique used in aluminum?
a) Increase penetration
b) Reduce distortion
c) Improve appearance
d) Increase deposition rate
With Correct Answers (Verified Answers) Plus
Rationales 2026 Q&A | Instant Download Pdf
1. Which aluminum alloy series is most commonly used for welding
in structural applications?
a) 1XXX
b) 2XXX
c) 5XXX
d) 7XXX
The 5XXX series contains magnesium, providing good corrosion
resistance and weldability, making it ideal for structural welding.
2. What is the primary concern when welding aluminum compared
to steel?
a) Higher melting point
b) Oxide layer formation
c) Rapid heat conduction
d) Lower ductility
Aluminum conducts heat quickly, making it difficult to maintain
proper weld pool control.
3. What gas is typically used for GTAW (TIG) welding of aluminum?
a) Oxygen
b) Carbon dioxide
c) Argon-Helium mix
d) Argon
, Argon provides an inert shielding atmosphere to prevent oxidation
during aluminum welding.
4. Which cleaning method is recommended before welding
aluminum?
a) Grinding with steel brush
b) Solvent degreasing only
c) Mechanical cleaning with stainless steel brush
d) Acid etching only
Aluminum forms a refractory oxide layer that must be removed
mechanically before welding.
5. What is a characteristic of 5356 filler metal?
a) Poor corrosion resistance
b) High strength and corrosion resistance
c) Only suitable for brazing
d) Low melting point
5356 is widely used for aluminum structural welding due to its
strength and corrosion resistance.
6. Preheating aluminum prior to welding is typically:
a) Required for all alloys
b) Never required
c) Used for thick sections to reduce cracking
d) Used only for 1XXX series
Preheating helps reduce thermal gradients in thick aluminum
sections, minimizing hot cracking.
7. What is the typical thickness range for fillet welds in aluminum
structures?
a) 1/16” to 1/8”
, b) 1/8” to 1/2”
c) 1/2” to 1”
d) Over 1”
Fillet weld size depends on the thickness of members; 1/8” to 1/2”
is standard for structural aluminum.
8. When using GTAW on aluminum, what is the recommended
polarity?
a) DCEN (Direct Current Electrode Negative)
b) ACEN
c) AC (Alternating Current)
d) DCEP (Direct Current Electrode Positive)
AC allows cleaning action and good penetration, which is essential
for aluminum TIG welding.
9. Which defect is common in aluminum welds due to
contamination?
a) Underfill
b) Porosity
c) Burn-through
d) Overlap
Contamination from oils, moisture, or oxide layers traps gas in the
weld, causing porosity.
10. Why is back-step welding technique used in aluminum?
a) Increase penetration
b) Reduce distortion
c) Improve appearance
d) Increase deposition rate
