Mechanical Behavior of Materials

Recommended Prerequisites

Materials Science, Applied Mechanics, Strength of Materials, Introduction to Mechanical Design.

Teaching Methods

Theoretical classes present and develop topics that correspond to the course syllabus. The theoretical-practical classes aim to consolidate the concepts taught in the theoretical classes based on concrete problems and simultaneously encourage active participation by students through self-learning and self-criticism by proposing strategies for their resolution. Students also participate in a limited number of practical laboratory classes on mechanical tests where they will have to prepare reports.

Learning Outcomes

The aim is to provide the students with scientific and technical knowledge on the mechanical behavior of materials, namely: brittle and ductile fracture, fatigue and the interaction of materials with the environment, particularly creep and stress corrosion. Fracture and fatigue in composite materials will also be addressed. Students should acquire the skills to understand the phenomena described and to act independently in quality control activities, design and material selection, critical analysis of defective parts and maintenance.

Work Placement(s)

No

Syllabus

Fracture of materials: Stress intensity factor; plasticization at crack tip; Fracture toughness; Elastoplastic parameters: CTOD and Integral J; Experimental determination of K1c, CTOD and J integral; Interlaminar fracture of composite materials; Failure assessment diagram and crack driving force.

Fatigue of materials: Fatigue damage assessment using local stress-strain approach; Crack propagation curves; Crack closure and fatigue propagation threshold; Laws of fatigue crack propagation; Effect of overloads; Stress corrosion and da/dt - K curves; Fatigue with corrosion; Crack initiation from notches; Fatigue in composite materials: damage characterization and main parameters.

Creep: Creep tests; Creep for long lives; Stress relaxation; Stresses and strains for pure bending of a rectangular section bar. Wear: Topography of surfaces; Wear by: abrasion, adhesion and erosion.

Head Lecturer(s)

Paulo Nobre Balbis dos Reis

Assessment Methods

Assessment
Synthesis work: 10.0%
Laboratory work or Field work: 15.0%
Exam: 75.0%

Bibliography

Broeck, D., (1986) Elementary Engineering Fracture Mechanics. 4^th edition, Martinus Nijhoff Publishers, Dordrecht - Netherlands.

Hertzberg, Richard W., Vinci, Richard P., Hertzberg, Jason L. (2020) Deformation and Fracture Mechanics of Engineering Materials, 6^th edition, John Wiley & Sons Ltd. United States of America.

Barsom, J.M., Rolfe, S.T. (1999) Fracture and Fatigue Control in Structures: Applications of Fracture Mechanics, 3^rd edition, ASTM International, West Conshohocken, Pennsylvania - EUA.

Talreja, R., Varna, J. (2023) Modeling damage, fatigue and failure of composite materials, 2^nd edition, Woodhead Publishing, Sawston, Cambridge - United Kingdom.

Spagnoli, A. (2020) Fatigue and Fracture of Non-metallic Materials and Structures. MDPI - Multidisciplinary Digital Publishing Institute, Basel - Switzerland.