The objective of this course is to provide the concepts, procedures, decision analysis techniques necessary to design machine elements commonly found in mechanical devices.
The course aims to provide students of the knowledge and understanding of the criteria of structural design of the main mechanical members.
1st part – Fundamentals of machine design
Recalls of statics and kinematics of rigid bodies. Tension and strain in solids. Equilibrium of deformable bodies. Loads diagrams. Area of cross sections. Theory of the beams (subjected to tensile, compression, shear, bending, torsion). Effects superposition. Equation of the elastic line. Conventional structural materials (mechanical properties).
2nd part – Criteria of structural design
Static strength of materials. Ideal or equivalent stress. Strength criteria for ductile materials. Strength criteria for brittle materials. Safety condition: Limit stress, Safety factor, Admissible stress.
Notches and their effect. Elastic and experimental stress concentration factor. Safety condition in presence of notches.
Fatigue in metallic materials. Fatigue spectra.
High cycle fatigue: Wöhler curves; Influence of the mean stress; Notches and their influence; Size factor; Surface factor. Safety condition for stresses of constant amplitude. Safety condition for stresses of variable amplitude: Cumulative damage.
Long columns with central loading. Euler column formula.
De Paulis A., Manfredi E., Costruzione di macchine: Criteri di base e applicazioni principali, Pearson Italia - Milano, 2012
Hibbeler R.C., Meccanica dei solidi e delle strutture: teoria ed applicazioni, Pearson Italia - Milano, 2010
Vergani L., Meccanica dei materiali, Mc-Graw Hill Companies, 2006
Nerli G., Costruzione di macchine, Noccioli Editore - Firenze, 2005
Shigley J.E., Progetto e costruzione di macchine, 2a ed., McGraw-Hill, 2009
Chirone, E., Tornincasa, S., Disegno tecnico industriale, Ed. Il Capitello - Torino, 2011
Ricevimento: The teacher is available for the students at the end of lessons and by appointment
MARGHERITA MONTI (President)
ROBERTO RAZZOLI (President Substitute)
september 25th 2020
Written and oral examination. The written test regards the solution of one exercise. The oral examination consists of two questions on theory. A positive evaluation of the written test is necessary condition to access the oral examination.
Suggested pre-requisite: Applied Mechanics, Technical Drawing