Slow Cheetah
Mechanical Engineering Design Learning notes
(Reference: Shigley’s Mechanical Engineering Design Textbook)
Manufacturing cost is highly dependent on tolerance. In my previous experience, when estimating the facility cost, we normally convert that into a value equalling to a coefficient times the cost of the metals.
The heat Treatment of Steel
- Annealing: soften a material and make it more ductile, to relieve residual stresses, and to refine the grain structure.
- Quenching: rapid cooling, prevent phase-changing.
- Tempering: stress relieving.
Key properties: Young’s modulus (stress/strain), density, strength(MPa)
Temperature effects
Thermal expansion, change the normal strain.
Failure analysis
for ductile behaviour: distortion-energy theory (Coulomb-Mohr method)
Crack modes: opening crack propagation (Most common), sliding, tearing.
Fatigue failure (Could combine with liquid-soild interaction simulation? How to determine failure criterion? Frequency? Humidity? etc.)
Fatigue-life methods: stress-life, strain-life, linear-elastic.