29773 - Metallurgy T

Learning outcomes

The primary focus of the Metallurgy T program is to provide undergraduates with a fundamental knowledge-base associated with metals-processing, their properties, and their selection and application. The main learning objectives are: (i) how to select metallic materials for producing mechanical components working in a given service condition; (ii) how to relate their mechanical properties to the microstructure, induced by the production process and heat treatment; (iii) how to identify the reason for malfunctioning related to material features. Particular attention will be devoted to the presentation of the main microstructural,fractographicandmechanical characterization techniques for steels and light alloys.

Course contents

Course introduction. Presentation of course contents, teaching method and materials, as well as of assessment methods.

Mechanical testing and properties: tensile, hardness, toughness, fatigue, creep, friction and wear. Microstructural and fractographic analyses of metals.

Alloys and phase diagrams. Phases and structural constituents. Cooling curves, phase and lever rules. Solidification and cooling of binary metal alloys.

Solidification microstructure and defects. Nucleation and growth of pure metals and alloys. Influence of solidification microstructure and defects on the mechanical properties. Solidification structures control methodologies.

Crystal structure and imperfections in the atomic arrangement. Main crystal structures of metals and their effect on mechanical properties. Point defects and atoms movements in materials (diffusion).

Elastic and plastic deformation of metals. Elastic deformation: physical, engineering and metallurgical meaning of the elastic modulus and variables of influence. Plastic deformation of metals based on the dislocations theory.

Strengthening mechanisms of metals. Solid solution, strain hardening, grain refinement, precipitation and dispersion.

The Fe-C phase diagram. Phases and micro-constituents. Cooling and solidification of steels iand cast irons in equilibrium conditions. Equilibrium microstructures of carbon steels. Short overview of cast irons and stainless steels.

Designation and classification of the main metallic materials according to EURONORM

Phase transformation in steels. Ferritic, pearlitic, bainitic and martensitic phase transformations. TTT and CCT curves.

Heat treatments of steels: annealing, normalizing, quenching, tempering.

Thermochemical diffusion treatments of steels: carburizing and nitriding for the enhancement of friction/wear and fatigue properties.

Aluminium alloys. Designation. Alloying elements. Heat treatments. Physical, mechanical and technological properties. Main application fields.

Case studies and selection criteria of metals as a function of the service conditions.

Readings/Bibliography

Course Material consists of slides and notes in Italian, with a glossary of the main Italian / English terms.

All the slides used by the teacher are available in the VIRTUALE repository, as password-protected pdf files (in Italian). Example of the exam questions are also given.

Donald R. Askeland, P Webster "The science and engineering of materials", Chapman & Hall

W.D. Callister, “Fundamentals of Materials Science and Engineering”, J.Wiley and Sons (2001)

Teaching methods

Classroom lectures according to the timetable as well as to health and safety protocols.

Interactive learning tests on the main concepts.

Audiovisuals on the main (i) concepts and processes, (ii) metallurgical lab methods.

Assessment methods

Examination in English can be arranged by previous contact with the teacher.

The final examination consists of a test, aiming at assessing if the student learned how (i) to select metallic materials and treatments for producing mechanical components that work in a given service condition and how (ii) to identify the reasons for malfunctioning related to material features.

The examination consists of two parts:

• Part 1. A multiple choice test, online, consisting of 30 questions, 4 options per question (45 minutes). If the final grade of the test is equal to or higher than 18/30, the student will be admissed to the further oral examination. Examples of questions are available in the teaching material available in the VIRTUALE repository.
• Part 2. An oral examination with 2 open questions (20 minutes).

The student will access the second part of the exam (oral examination) only if he/she achieves at least 18 correct answers in the first part (multiple choice test). Answers to multiple choice questions will be evaluated as follows:

• +1 pt for each correct answer
• 0 pt for each missing or wrong answer

The final grade will be calculated as average of the grades reached in Part 1 and Part2. The grade is expressed in /30.The minimum score for passing the exam is assigned if satisfactory knowledge of all the subjects is assessed and there are no serious deficiencies.

Specific instruction on exam management (either online or offline) are available in VIRTUALE repository.

Textbooks and personal electronic devices are not allowed during the examination.

Examinations schedule is available in advance on the University of Bologna web site AlmaEsami. Students willing to take the exam must join the student list on the web site AlmaEsami, carefully considering deadlines for student list opening and closing. Students are required to show their own ID before taking the exam.

Teaching tools

Classrooom lectures with both PC/slide projector and blackboard. Students are encouraged to attend Metallurgy classes in order to improve their final learning outcomes.

The course attendance is not mandatory but strongly recommended.

Office hours

See the website of Lorella Ceschini