Strengthening
they are Solid Solution (Alloying), Manipulation of Grain Size, % Cold Work (Strain Hardening)
the 3 methods of strengthening
crystallographic plane and direction alone which dislocation motion occurs
what is a slip system?
Decreasing the grain size of a metal generally increases this mechanical property.
What is strength?
Cold working increases the number of these defects in the crystal structure, which resist dislocation motion.
What are dislocations?
This type of deformation occurs when a metal is shaped below its recrystallization temperature.
What is cold working
How do the attributes of a material get changed when it is Cold Worked
Increased Tensile Strength & Yield Strength
Decreased Ductility
The Schmid’s Law equation is used to calculate the stress required for slip. It is written as:
What is τ = σ * cos(φ) * cos(λ)?
According to the Hall-Petch relationship, reducing this structural feature increases a material's strength by creating more barriers to dislocation motion.
What is grain size?
In steel, the presence of this interstitial impurity significantly increases hardness but can also make the metal more brittle.
What is carbon?
Cold working is typically performed at this temperature range.
What is below the metal’s recrystallization temperature?
This equation relates the yield strength of a material to its grain size, following the Hall-Petch relationship.
What is σy = σ₀ + k * d^(-1/2)?
This crystal structure is considered the most ductile because it has the highest number of slip systems.
What is face-centered cubic (FCC)?
This term describes the phenomenon where grains grow larger when held at high temperatures for extended periods.
What is grain growth?
Adding impurity atoms to a metal strengthens it by distorting the crystal lattice and impeding dislocation motion in this strengthening mechanism.
What is solid solution strengthening?
This equation calculates the percentage of cold work based on the original and final cross-sectional areas.
What is % Cold Work = [(A₀ - Af) / A₀] × 100%?
This type of strengthening occurs when dislocations entangle and interfere with each other, increasing resistance to deformation.
What is dislocation strengthening?
In an FCC material, slip occurs most commonly on this family of planes and directions.
What is {111}⟨110⟩?
According to this equation, σ_y = σ₀ + k * d^(-1/2), what's the variable that represents the average grain diameter.
What is d?
This impurity, often found in aluminum alloys, can weaken grain boundaries and reduce mechanical properties.
What is hydrogen?
In metals like aluminum, excessive cold working can lead to the formation of this type of defect, which can cause failure under stress.
What are microcracks?