Electrode Coating Materials And Characteristics Flashcards
Carbon steel electrodes with different properties are obtained by adding ____________ rather than changing the ___________.
Alloying elements
Core wire.
This is to say the core wire is not responsible for the characteristics of the filler metal, it is the alloying elements.
What impact do oxides have on the base metals when welding?
Oxides are low in tensile strength and ductility and tend to reduce the normal properties of the base metals.
Name some functions of the flux coating on a mild steel SMAW electrode.
Improves weld appearance.
Provides easier arc striking.
Helps maintain a stable arc and regulates the depth of penetration. **
It affects the arc length and welding current.
Influences puddle fluidity and in turn controls the welding position which the electrode can be used.
Cellulose (0, 1) is a product of _________, which breaks down to release ___________ and __________. It also provides a protective gas shield over the weld puddle.
Wood pulp.
Hydrogen and carbon dioxide.
Rutile (2, 3, 4) is a mineral that consists of _________, usually with a small amount of iron. These minerals act as _____________ and ______________.
Titanium dioxide
Arc stabilizers and slag formers.
Iron oxide (7) is found in the form of iron ore, such as magnetite and hematite. It’s main purpose is to be a _______________.
Slag former.
Iron powder is added to electrodes coatings to increase the _____________________.
Deposition rate.
Calcium carbonate is found in _________ and is an important ingredient of electrodes that produce a _____________ weld deposits. It breaks down the arc to produce _________ that protects the molten weld metal and lowers the __________ content of the arc atmosphere.
Limestone
Low hydrogen-type
Carbon dioxide
Hydrogen content
Potassium silicate is used in electrode flux coatings as an ____________ and as a _________ to keep the flux from crumbling off the core wire.
Arc stabilizer
Binder
What are the characteristics of fast freeze electrodes? Give an example of one.
-Deposit weld w/ the ability to solidify quickly
-Great for overhead and vertical welds
-Deep penetrating rod w/ little slag produced.
E6010 (E4310)
What are fast fill electrodes? Give an example of one.
-Designed to deposit large amounts of filler metal at a fast rate
-Contain large quantities of iron powder
-Best suited for flat and horizontal positions
-It’s used for production welding
-Jet rod E7024 (E4924)
What are fill freeze electrodes? Give an example of one.
-Rapid deposition of narrow, shallow penetrating weld bead
-Crater follows behind the arc
-Suited for light-gauge sheet metal (DCEN specifically produces shallow penetration)
-E4913 (E7013)
A heavy iron powder in the coating means you should weld in the __________ and __________ positions. An electrode with less iron powder is best suited for __________ and _________ positions.
Flat and Horizontal
Overhead and Vertical
