WELD-251 Welding Metallurgy

Credits 3 / 4 Contact Hours
Pre-requisite: Placement into ACRD 080 ; WELD 143 .
This course will cover the weldability of carbon steel, low alloy steel, high strength low alloy steel, and related tool steels along with filler metal chemistry. The impact that welding variables have on the microstructure of the weld joint and changes in thermal cycle, flux composition, contamination, and chemical reactions in the molten weld pool will be addressed. Students will be exposed to how the microstructures of the weld and the heat affected zone are defined by these changes and how these variables can determine the mechanical properties of a weldment.

Course Outcomes
Discuss how steel is made and how it is affected during the welding process.

Discuss how steel is made.
Discuss the effects of the welding arc.
Discuss how and why the welds are stronger then the base metal.

Identify the properties of metals.

Discuss the fundamentals of crystals and importance of crystalline structure.
Identify mechanical properties of metals.
Discuss the fracture of metals and fracture toughness.

Explore the effects of alloying elements.

Identify steels based on alloying elements.
Discuss the chemical and mechanical properties of steel.
Discuss steel specifications and standard industry accepted practices.
Discuss carbon and alloy steel used in welded construction.

Explore different welding methods and processes.

Identify cutting and welding processes as related to a AWS standard.
Identify the heat sources for welding and cutting.
Discuss the application of different welding processes.

Identify filler metal compositions and specifications.

Identify filler metal specifications from AWS standards.
Identify chemical composition and how they are related to different weld processes.
Identify the correct filler metal composition for a selected base metal.

Investigate the uses of fluxes, slags, and gasses for welding.

Discuss the oxidation of molten steel.
Discuss the prevention of oxidation of steel while welding.
Discuss shielding of the welding process from air.

Discuss the weldability of iron and steel.

Discuss the transformations in weld metal.
Discuss a typical fusion weld in steel.
Discuss the predictions of microstructures in the heat affected zones of welds.
Discuss weld dilution due to joint design.

Discuss temperature changes in welding.

Evaluate the effects of the temperature and time in welding.
Discuss control of temperature in fusion welding.
Discuss preheat and post heat of metals.

Demonstrate destructive and non-destructive test methods.

Discuss non-destructive testing methods used in the welding industry.
Discuss destructive testing methods use in the welding industry.
Preform destructive and non-destructive tests on weld samples.