Base and Filler Metals Flashcards

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

Answer: E308L

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

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

Answer: Act as a deoxidizer for mildly contaminated base metals

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

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

Answer: Structural carbon steel

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

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

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

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

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

Answer: High-temperature pressure piping and boilers

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

When selecting filler metal for a specific base metal, which document provides the primary guidance?

Answer: The applicable welding procedure specification (WPS)

The WPS specifies the approved filler metal, process, and parameters qualified for a given base metal.

Nickel alloy filler metals are used primarily to weld base metals that require which characteristic?

Answer: Excellent corrosion and high-temperature resistance

Nickel alloys provide outstanding resistance to corrosive environments and maintain strength at high temperatures.