B8045 - MATERIALI METALLICI CON LABORATORIO

Learning outcomes

The course provides fundamental knowledge of the production, processing, characterization, and application of metallic materials, with particular emphasis on the relationships among processing, microstructure, properties, and performance. Laboratory activities allow students to experimentally investigate and apply the theoretical concepts covered during the course.

Course contents

Learning Prerequisites

Students are expected to possess the following background knowledge:

• Elementary mathematical functions (powers, roots, exponential and logarithmic functions), solution of algebraic equations, derivatives, and basic concepts of differential calculus. (Reference course: Mathematics with Exercises).

• Knowledge of the main physical and mechanical quantities, their units of measurement, and the relationships among them. Mass and energy balances, units commonly used in chemical reactions, heat transfer, and bond energies. Unit conversions within the International System of Units (SI). (Reference course: Physics with Exercises).

• Chemical reactions and their balancing, atomic structure, and the nature of chemical bonding. (Reference course: General Chemistry).

• Fundamental principles of thermodynamics. (Reference course: Physical Chemistry).

• Main crystal structures of metallic materials and their influence on plastic deformation mechanisms; mechanical properties of materials and related testing methods; phase diagrams of binary metallic alloys; solidification theory and solidification defects; equilibrium microstructures of Fe-C alloys; strengthening mechanisms; basic concepts of corrosion and wear phenomena. (Reference course: Physical Metallurgy and Materials Technology with Laboratory).

Course Introduction

Presentation of the learning objectives, course contents, teaching organization, laboratory activities, teaching materials, and assessment methods.

Production of Metallic Materials

Extraction and production of metals. Primary and secondary metallurgy, including steelmaking and light-alloy production. Recycling processes for metallic materials. Sustainability of metallurgical processes, circular economy principles, and issues related to the supply of Critical Raw Materials (CRMs).

Manufacturing Processes for Metallic Materials

Definition and classification of the main manufacturing processes for metallic materials.

• Bulk and sheet metal forming processes, including forging, hot and cold rolling, extrusion, and drawing.

• Casting processes using expendable moulds (sand casting) and permanent moulds (gravity casting, die casting, and continuous casting).

• Fusion welding processes, including gas welding, electric arc welding, plasma welding, laser welding, and friction welding.

• Additive Manufacturing processes, with particular focus on Powder Bed Fusion (PBF) and Direct Energy Deposition (DED) technologies.

Iron-Carbon Diagram and Ferrous Alloys

Review of the iron-carbon phase diagram: phases and microstructural constituents. Solidification and cooling phenomena in steels under thermodynamic equilibrium conditions. Typical steel microstructures as a function of carbon content. Effect of the main alloying elements. Designation and classification of steels according to European standards.

Phase Transformations in Steels

Isothermal and continuous-cooling transformations. Ferritic, pearlitic, bainitic, and martensitic transformations. Bain diagrams and TTT (Time-Temperature-Transformation) and CCT (Continuous Cooling Transformation) diagrams.

Heat Treatments and Thermochemical Treatments of Steels

Full annealing, isothermal annealing, recrystallization annealing, normalizing, martensitic quenching, and tempering. Quenched-and-tempered steels. Thermochemical treatments, including carburizing and nitriding. Steels for thermochemical treatments. Influence of heat and thermochemical treatments on mechanical properties, wear resistance, and fatigue performance.

Stainless Steels

Definition and classification of stainless steels. Main families: austenitic, ferritic, martensitic, duplex, and precipitation-hardening stainless steels. Chemical composition, heat treatments, physical and mechanical properties, and major industrial applications.

Aluminium Alloys

Classification and designation of casting and wrought aluminium alloys. Effect of alloying elements. Strengthening mechanisms. Heat treatments, microstructure, physical and mechanical properties, and major industrial applications.

Titanium Alloys

Classification and designation of titanium alloys. Mechanical and physical properties. Effect of alloying elements. Microstructures, heat treatments, and major industrial applications.

Degradation Phenomena in Metallic Materials

Behaviour of metallic materials under static, dynamic, and cyclic loading conditions. Fatigue and creep phenomena. Introduction to corrosion and material-environment interactions. Failure analysis through industrial case studies.

 

Laboratory Activities

Metallographic Analysis

Fundamentals of quantitative metallography and image analysis techniques. Sampling procedures and specimen preparation for microstructural characterization. Metallographic preparation and optical microscopy of heat-treated steels (annealed, normalized, quenched, and tempered). Hardness profile measurements on carburized and nitrided specimens.

Microstructure of Non-Ferrous Alloys

Observation and interpretation of typical microstructures of aluminium alloys produced through conventional manufacturing routes and Additive Manufacturing technologies.

Thermal Analysis

Principles of Differential Scanning Calorimetry (DSC). Processing and interpretation of DSC curves of aluminium alloys. Evaluation of the effects of high-temperature exposure on aluminium alloys through degradation curve analysis.

Microstructural Characterization by Scanning Electron Microscopy (SEM)

Sampling procedures and specimen preparation. Microstructural characterization using Scanning Electron Microscopy (SEM) and, where applicable, Energy Dispersive Spectroscopy (EDS). Interpretation of microstructures in relation to processing conditions and applied heat or thermochemical treatments.

 

Readings/Bibliography

Electronic teaching materials provided by the instructor (lecture slides are made available to students on Virtuale (virtuale.unibo.it) as password-protected PDF files). The teaching materials also include sample exam papers.

Recommended reference texts:

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

D.R. Askeland, P. Webster "The science and engineering of materials", Chapman & Hall (2007)

Teaching methods

The course consists of lectures and laboratory activities.

Lectures are delivered in person and make use of audiovisual materials to illustrate the main theoretical concepts, manufacturing technologies, and industrial case studies discussed during the course. To promote active student participation and support formative assessment, interactive quizzes and guided discussions may be used throughout the lectures.

Laboratory activities provide students with the opportunity to experimentally apply the theoretical concepts covered during the course through microstructural characterization, thermal analysis, and evaluation of the properties of metallic materials.

Due to the nature of the laboratory activities (Module 2), all students are required to complete Modules 1 and 2 of the University of Bologna online safety training and to attend Module 3, which provides specific training on health and safety in study and laboratory environments, according to the procedures established by the University.

Attendance at all laboratory sessions is mandatory. In order to fulfil the attendance requirement, students must participate in all scheduled laboratory activities.

This course contributes to the University of Bologna's Teaching Innovation Programme.

Assessment methods

The assessment is designed to verify the achievement of the intended learning outcomes in terms of knowledge, application skills, and critical thinking related to the main topics covered in the course.

In particular, the examination aims to assess:

• knowledge of the main production, manufacturing, and processing routes for metallic materials;
• the ability to interpret the Fe-C phase diagram and describe phase transformations in steels, including solidification phenomena, isothermal and continuous-cooling transformations, reference microstructures, and the effects of the main heat and thermochemical treatments;
• knowledge of the main families of stainless steels, aluminium alloys, and titanium alloys, including designation systems, chemical composition, microstructure, heat treatments, mechanical and physical properties, and fields of application;
• the ability to identify and discuss the main degradation and failure mechanisms of metallic materials, with particular reference to fatigue, creep, and failure analysis;
• the ability to select and critically discuss the main microstructural and mechanical characterization techniques for metallic materials employed during laboratory activities.

Assessment is based on a final examination, to be taken after completion of the course and upon registration through AlmaEsami. The examination consists of three components:

1. a written test covering the Metallurgy module;
2. laboratory reports in PowerPoint format related to the laboratory activities;
3. an oral examination covering both the Metallurgy module and the laboratory activities.

Written Test

The written test consists of a multiple-choice questionnaire comprising 30 questions. Each question has four possible answers, of which only one is correct. The duration of the test is 45 minutes.

The score, expressed on a 30-point scale, is calculated as follows:

• +1 point for each correct answer;

• 0 points for each unanswered question;

• -0.25 points for each incorrect answer.

A minimum score of 18/30 is required to pass the written test. Passing the written test is a prerequisite for admission to the oral examination and for the final evaluation of the laboratory reports. The written and oral examinations must be taken during the same examination session.

During the written test, the use of notes, textbooks, teaching materials, digital resources, or calculators is not permitted.

Laboratory Reports

Assessment of the Laboratory module is based on laboratory reports in PowerPoint format prepared by students on the laboratory activities carried out during the course.

The reports are intended to evaluate the student's ability to correctly describe the experimental procedures adopted, interpret the results obtained, discuss the observed microstructures, and select the most appropriate characterization techniques for the investigation of metallic materials.

Deadlines for submission of the laboratory reports for each examination session will be communicated in advance through the Virtuale platform.

Oral Examination

The oral examination consists of open-ended questions covering the topics discussed in the Metallurgy module and the laboratory activities and has a maximum duration of 60 minutes.

The oral examination is intended to assess the student's mastery of the course contents, ability to establish connections among different topics, correct use of technical terminology, and capacity to critically discuss the relationships between processing, microstructure, properties, and performance of metallic materials.

During the oral examination, the consultation of notes, textbooks, teaching materials, or digital resources is not permitted.

Final Grade

The final grade, expressed on a 30-point scale, is determined on the basis of:

• the laboratory reports;
• the oral examination.

The final evaluation takes into account the level of knowledge achieved, the ability to apply theoretical concepts to practical cases, the correctness of the interpretation of experimental results, the ability to connect different course topics, clarity of presentation, and mastery of technical and scientific terminology.

Examples of both written and oral examination questions are available in the teaching materials provided through the Virtuale platform.

Students with Specific Learning Disabilities (SLD) or Disabilities

Students with temporary or permanent disabilities, or with specific learning disabilities (SLD), are encouraged to contact the relevant University office well in advance. The office will propose any necessary accommodations, which must be submitted to the instructor for approval at least 15 days before the examination. Approval will be granted provided that the proposed accommodations are consistent with the intended learning outcomes of the course.

Use of Generative Artificial Intelligence

With regard to assessment activities, the use of generative Artificial Intelligence (AI) is not permitted during examination tests. Any unauthorized use constitutes a violation of academic integrity.

For laboratory reports, limited, declared, and non-substantial use of generative AI is permitted for language support, summarization, or text revision purposes. Substantial use of AI for data processing, interpretation of results, technical discussion, or autonomous preparation of significant portions of the report is not permitted. Any use of AI tools must be explicitly declared by the student.

Teaching tools

Classrooom lectures with both PC/slide projector and blackboard. Online lectors via Teams. Interactive sessions for learning assessment (no grading). Students are encouraged to attend Metallurgy classes in order to improve their final learning outcomes. The course attendance is not mandatory and it does affect the final examination score.

Students with learning disorders and\or temporary or permanent disabilities: please, contact the office responsible (https://site.unibo.it/studenti-con-disabilita-e-dsa/en/for-students). As soon as possible so that they can propose acceptable adjustments. The request for adaptation must be submitted in advance (15 days before the exam date) to the lecturer, who will assess the appropriateness of the adjustments, taking into account the teaching objectives.

Office hours

See the website of Gianluca Di Egidio