Certified Welder Base and Filler Metals 3

Question 1

Which filler metal is preferred when welding austenitic stainless steel to minimize sensitization?

Accepted Answer

E308L

Answer

E308L has a low carbon content (≤0.04%) that reduces carbide precipitation and sensitization in the heat-affected zone.

Question 2

What is the primary purpose of adding silicon (Si) to ER70S-6 wire compared to ER70S-2?

Accepted Answer

Act as a deoxidizer for mildly contaminated base metals

Answer

Higher silicon in ER70S-6 provides stronger deoxidation, making it suitable for welding base metals with rust or mill scale.

Question 3

A base metal identified as ASTM A36 is classified as which type of steel?

Accepted Answer

Structural carbon steel

Answer

ASTM A36 is a common structural carbon steel with a minimum yield strength of 36 ksi used in construction.

Question 4

What does 'weldability' of a base metal primarily refer to?

Accepted Answer

The ease with which a metal can be welded with acceptable properties and without defects

Answer

Weldability encompasses the metal's ability to be welded under given conditions to produce sound joints meeting service requirements.

Question 5

Chromium-molybdenum (Cr-Mo) alloy steels are commonly used in which application?

Accepted Answer

High-temperature pressure piping and boilers

Answer

Cr-Mo steels offer excellent creep resistance and strength at elevated temperatures, making them ideal for boilers and high-pressure piping.

Certified Welder Practice Test