20.6 Chapter Conclusion
David Colameco, M.Ed.
Summary
Ferrous metals are metals that contain iron as one of the primary elements in its chemical composition. As you start welding in your welding school, ASTM A36 steel is usually the metal you will start welding with. A36 is easy to weld and used widely in the fabrication industry for structural applications. Ferrous metals can be welded using a variety of welding processes that are available in your welding program such as SMAW, GMAW, FCAW, GTAW, and SAW in addition to many other welding processes. Some weldments will use GTAW for the root pass and another process for the interpasses and cover passes. This makes learning as many welding processes as you can while in school very important.
Other ferrous metals with higher contents of alloying elements, such as stainless steels and higher contents of carbon such as cast iron require more skill than ASTM A36 to weld. These metals require more preparation and attention to the details of welding. Stainless steels require more attention to cleaning, monitoring interpass temperatures, and use of shielding gasses. Cast irons also require more cleaning for castings that have been used and have been exposed to greases and oils, and they also require preheat and attention to temperatures for quality welds. Welding procedure specifications or best practices when not welding to a code are very important to follow to ensure a quality weld.
Review Questions
- A weld that is made without the addition of filler metal is a(n)?
- Quality weld
- Autogenous weld
- Inexpensive weld
- Metallurgically pure weld
- Women welders were first used in large numbers to support the war effort for which war?
- Civil War
- War of 1812
- World War II
- Vietnam War
- Which alloying element is the main contributor to corrosion resistance in stainless steel?
- Carbon
- Chromium
- Nitrogen
- Nickel
- Welding was first developed using _______ as a heat source.
- Electricity
- Gas fuels
- Laser beams
- Electrons beams
- Arc welding was brought to the rural areas of America through which government initiative?
- Rural Electrification Administration
- Department of Agriculture
- Works Progress Administration
- Wind mill initiative
- SMAW electrodes were coated with flux after early researchers likely found?
- A friend of a researcher had extra flux that needed to be sold
- SMAW electrodes do not have a flux coating
- Rusty wire electrodes worked better
- It was easier to add identifying colors and writing to flux and not bare metal
- If a fabrication fails where public safety is threatened, who gets interviewed during the investigation? Select all that apply.
- Authors of fabrication records
- Welders who worked on the fabrication
- Engineers who designed the fabrication
- No one gets interviewed or investigated
- Ferrous metals are used in which types of fabrications? Select all that apply.
- Pipes
- Bridges
- Buildings
- Ships
- What is the heat affected zone?
- The base material that expanded and shrunk due to the heat of welding
- The base material next to the weld that has changes in its grain structure and properties from the heat of welding
- Metal is not affected by heat, the heated affected zone is not a welding term.
- The distance from the hot weld bead where a welder will start sweating from the heat of welding
- Wrought steel is made at a foundry by melting iron and its ingredients together and then? Select all that apply.
- Rolling the hot metal ingot into thinner and thinner metal until the desired shape is formed
- Heat treating the metal
- Cutting the material to size
- Wrought steel is not produced in a foundry
- Which welding process(es) does not use a shielding gas supplied from a bottle or other pressurized container. Select all that apply.
- GMAW-S
- SMAW
- FCAW-S
- FCAW-G
- Which welding process is primarily used for welds requiring high quality such as specialty alloys and critical welds?
- GMAW
- SAW
- GTAW
- FCAW
- Which welding process is specifically used for thin materials due to its low penetration?
- GMAW-S
- SMAW
- FCAW-S
- FCAW-G
- Which welding process is used to weld very thick materials for heavier industries such as bridge building, pipe fabrications and other very large fabrications?
- GMAW
- SAW
- GTAW
- FCAW
- Which semi automatic process is used for fabrication in the field?
- GMAW-S
- SMAW
- FCAW-S
- FCAW-G
- Why shouldn’t you use FCAW-S wire with a shielding gas?
- You should use FCAW-S with a shielding gas because more shielding the better.
- You should not use a shielding gas only because it is an unnecessary cost.
- FCAW-G doesn’t require shielding.
- The flux materials used to create the shielding gas do not react with the atmosphere and end up in the weld where they do not belong and affect the quality of the weld.
- Which welding process is not known for high deposition rates of filler metal?
- GMAW
- SAW
- GTAW
- FCAW
- Which welding process is probably not found in every welding program?
- GMAW
- SAW
- GTAW
- FCAW
- What shapes does stainless steel come in? Select all that apply.
- Plate
- Pipe
- C-Channel
- Angle iron
- The temperature range of 800 °F to 1600 °F should be avoided with stainless steel to prevent which condition?
- Discoloration only
- Sensitization
- Distortion only
- There is nothing special about that temperature range