ME 2820 Materials Processing
April 3, 2019: Exam Review
Exam 1 to be held next Tuesday April 9
Material structure → properties, heat treating, casting
Mid-term evaluations through next Tuesday
Structure → Properties of Materials
Ashby charts for materials
selection
High-temperature: grain
sliding, diffusional creep
Engineering/true stress-strain
Polymer failure: necking,
extension
Temperature effects: modulus,
yield stress, ductility,
toughness
Metal dislocation dynamics:
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Effect of precipitates
Grain size effect
Effect of temperature
Worcester Polytechnic Institute
Heat Treating Materials
Reading a phase diagram crystal structure
Solution heat treating:
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Steel: austenitize
Aluminum etc: solutionize
T-T-T diagrams and
transformations
Steel: pearlite, bainite,
martensite; hardening,
tempering
Cooling rate thresholds
Dimensional analysis
Dimensionless cooling curves
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Heat transfer coefficient
Biot, Fourier numbers
Estimating cooling time
Cooling/uniformity
Grain growth
Surface heat treat: nitriding,
carburizing, induction/flame
Aluminum: aging
Worcester Polytechnic Institute
Casting and Injection Molding
Casting types: die, sand,
investment, continuous, lost
foam, semi-solid
Quality problems:
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Large voids/cavities
Porosity
Hot tearing
Swells
Parting line flash
Swells
Misruns
Continuous-breakout
Other casting processes…
Heat transfer: mechanisms
and factors conrolling time
scale
Geometry design for quality
Economics
Worcester Polytechnic Institute