What are the equations for Stress, Strain, Hooke's Law, and Poisson's Ratio?
sigma = F/A
epsilon = (DeltaL)/L_0
E=sigma/epsilon
upsilon = (lateral epsilon)/(longitude epsilon)
A copper wire with a diameter of 2 mm is subjected to a tensile force of 500 N. Calculate the stress experienced by the wire.
(5*10^8)/pi Pa
What type of graph is this
A Eutectic graph
An alloy with 50wt%Mg - 50wt%Al at 400*C is in what State(s)?
gamma
What are the 2 components used to make chocolate?
Cocoa (solids) + Cocoa butter (fats)
What is the coordination number for a BCC structure?
8
True/False: Resilience is a material's ability to absorb energy before fracture, or all area under the stress-strain curve
False; This is Toughness.
Resilience is a Material's ability to absorb energy that can be released, or the area under ONLY the elastic region of the graph
For a titanium alloy, the stress at which plastic deformation begins is 100 MPa, and the modulus of elasticity at 25°C is 20 GPa.
a) What is the maximum load that can be applied to a specimen with a cross-sectional area of 2 cm² without plastic deformation?
b) If the original specimen length is 2 meters, what is the maximum length to which it can be stretched without causing plastic deformation?
a. 20,000 N
b. 2.01 m
What are the circled, starred, and boxed points called?
Circle: The proportional limit
Star: The point of maximum stress
Box: The Fracture point
What is the Phase Composition at about 90 wt% Ag at 800º F?
beta
= 95wt% Ag, 5wt% Cu ;
L= 82wt% Ag, 18wt% Cu
What type of grain boundary is this?
Amorphous grain boundary
What miller indices describe this family/density of planes?
{110}
What is a material with a low Young’s Modulus and a long plastic region on its stress-strain curve?
What is a Ductile Material
A steel beam with a cross-sectional area of 25 cm² is subjected to a tensile force of 100 kN. The beam stretches by 2 mm over its original length of 2 m. Calculate Young's modulus for the steel beam.
4*10^10 Pa
What is the max solubility of Cu in Ag at 700ºC?
~ 8%
At 1300ºC what wt% Ni should be added to Cu to ensure the liquid phase?
~ 40wt% Ni
Name each type of point defect:
What is an interstitial, substitutional, and vacancy point defect
What crystal system has the lattice parameters a = b = c; α = β = γ ≠ 90?
Rhombohedral
Which curves most likely correspond to a Metal, Ceramic, and Polymer respectively?
Orange : Metal
Green : Ceramic
Purple : Polymer
A rectangular sample of an unknown material has an initial length of 10 cm, and a cross-section of 2.1 cm X 2.1 cm dimensions. The sample is pulled in tension along the length (with the deformation described below all in the elastic region).
a. Calculate the strain if the sample is elongated to 10.5 cm.
b. With a Poisson’s ratio of 0.27, calculate the width in cm of the sample if the bar is elongated to 10.5 cm under applied stress.
c. Calculate the stress required (MPa) to elongate the sample to 10.5 cm if the elastic modulus is 2.10 GPa.
a. 0.05
b. 2.072 cm
c. 105 MPa
Determine the yield strength at a strain offset of 0.01?
~570 MPa
Find the Phases present and the phase fractions of an alloy at 500*C with 22wt% Mg, 78wt% Al
%alpha = 8/20 = 40%
%L = 12/20 = 60%
What is the importance of tempering in chocolate manufacturing?
Tempering forms stable cocao butter crystals, ensuring a smooth and shiny texture with less fracture. It is tempered to Form V
Which of the following would have the highest melting point: CaO, Sn, (C₂H₄)ₙ? Which has the lowest?
highest: CaO
lowest:
(C_2H_4)_n