Question

1. increasing the wire feed rate in gmaw or fcaw increases the ______ in the circuit.

a voltage
b slope
c current
d inductance
answer:

1. the fcaw process most commonly uses which type of shielding gas?

a carbon dioxide.
b argon.
c argon with 2% oxygen.
d argon with 10% carbon dioxide.
answer:

1. during gas metal arc welding of steel with 100% argon, undercutting can occur. what gas is often added to argon to prevent undercutting?

a helium.
b nitrogen.
c carbon dioxide.
d hydrogen.
answer:

Explanation:

1. In GMAW or FCAW, increasing the wire - feed rate increases the amount of metal being melted, which in turn increases the current in the circuit.
2. The FCAW process most commonly uses carbon dioxide as shielding gas.
3. When welding steel with 100% argon in GMAW, undercutting can occur. Adding carbon dioxide to argon can prevent undercutting as it changes the arc characteristics and improves the wetting of the weld pool.

Answer:

1. C. current
2. A. Carbon dioxide
3. C. Carbon dioxide