General information


Subject type: Mandatory

Coordinator: Julián Horrillo Tello

Trimester: Third term

Credits: 6

Teaching staff: 

Andreu Comajuncosas Fortuño

Teaching languages


This subject has been successfully enrolled by a number of foreign students, most of them from Italy. Classes are taught in Catalan, and students are expected to achieve a basic understanding of spoken Catalan. However, exams and practical reports can be written in Italian or other languages. Public questions in the classroom, and private questions to the lecturer, can also be posed in Italian or other languages.

Skills


Specific skills
  • EC9: Know the basics of science, technology and material chemistry. Understand the relationship between microstructure, synthesis or processing and material properties.

Description


Scientific foundations of the structure and properties of materials used in mechanical and electronic engineering.

It is recommended, but not essential, to have taken previous subjects in Physics and Chemistry.

The contents of this subject will be extended in later subjects.

Learning outcomes


In general, this subject contributes to the following learning outcomes specified by the subject to which it belongs:

- LO1: Relate the structure of materials with their properties and applications.

- LO2: Understand and apply material testing rules.

- LO3: Analyze and size structures.

LO9: Understand and put into practice the way and dynamics of teamwork.

- LO11: Carry out the assignments based on the basic guidelines given by the teacher, deciding the time to be used in each section, including personal contributions and extending the sources of information indicated.

At a more specific level, at the end of the course the student must be able to:

- Identify and distinguish the crystalline structures of the most used materials in engineering.

- Recognize the types of defects in crystal lattice, and explain their influence on the macroscopic properties of the material.

- Explain the mechanical, thermal and electrical properties of materials.

- Relate stress and strain in metals, ceramics and polymers.

- Interpret the phase diagrams of the most common binary alloys.

- Calculate the proportions of each phase from the phase diagram.

- Relate the microstructure of a material with the heat treatment to which it has been subjected, and with its properties.

- Relate the concentrations of dopants in a semiconductor with their electrical properties.

- Compare the properties of metallic, ceramic, polymer and composite materials.

Working methodology


The subject combines face-to-face classes in the classroom and practical classes in the laboratory.

In the classroom, the presentation of the theoretical concepts, the resolution of exercises and examples of application by the teacher will be alternated, and occasionally, the collaborative resolution and presentation on the board of some exercise by the students. students.

In the laboratory students will perform experiments related to the contents of the subject.

Students will have to devote additional time, non-contact, to the resolution of exercises, preparation of reports of laboratory practices and preparation of written tests.

Contents


1. Crystalline structures. Defects.

Description

Atomic bond: ionic, covalent, metallic and secondary. Link distance. Binding energy. Coordination number.

Crystalline systems. Unit cell. Bravais Networks.

Metal structures: body-centered cubic, face-centered cubic, compact hexagonal.

Ceramic structures: cesium chloride, sodium chloride, fluorite, cristobalite, corundum, graphite, football.

Polymer structures: polyethylene.

Semiconductor structures: silicon, gallium arsenide.

Positions and directions in the crystal lattice. Miller indices. Miller-Bravais indices.

X-ray diffraction.

Alloys. Hume-Rothery rules.

Punctual defects: vacant, interstitial atom, Schottky defect, Frenkel defect.

Linear defects: edge, helical and mixed dislocation. Burgers vector.

Surface defects. Polycrystalline materials.

Volume defects. Metallic glass.

Dissemination. Activation energy. Arrhenius equation.

Thermal production of point defects. Dilation due to the appearance of vacancies.

Fick's laws. Variation of the diffusion coefficient with temperature.

Stationary diffusion. Surface and intergranular diffusion.

Related activities

Exercise resolution.

First partial test.

Laboratory practices.

 

2. Mechanical properties of materials.

Description

Stress and deformation in metals. Tensile test. Elastic and plastic deformation. Elastic recovery.

Elastic limit. Young's module. Maximum tensile strength. Ductility. Tenacity. Hooke's law.

Fish coefficient. Shear.

Tension and deformation in ceramics and glass. Rupture module. Griffith crack pattern.

Stress and deformation in polymers. Effect of temperature and humidity.

Deformation at the microscopic scale. Sliding systems.

Hardness. Brinell and Rockwell stairs.

Creep. Dependence on voltage and temperature. Relaxation of tensions.

Viscosity. Supercooled liquids. Glasses. Tempered glass. Vulcanization. Elastomers.

Impact energy. Charpy's essay. Ductile and brittle fracture. Ductile-brittle transition temperature. Fracture toughness.

Fatigue. Fatigue resistance. Crack growth.

Non-destructive testing. Radiography. Ultrasound.

Related activities

Exercise resolution.

First partial test.

Laboratory practices.

 

3. Phase diagrams.

Description

Gibbs phase rule.

Diagram of a component.

Binary diagram. Total solubility. Characteristic microstructures.

Eutectic diagram. Total insolubility. Partial solubility.

Eutectoid diagram. Ferrite-cementite and ferrite-graphite.

Peritectic diagram. Congruent and incongruent fusion.

Lever rule.

Microstructures in slow cooling. Cast Iron. Acer.

Related activities

Exercise resolution.

Second partial test.

 

4. Thermal properties.

Description

Heat capacity. Specific heat at constant pressure and constant volume.

Thermal expansion. Linear expansion coefficient.

Thermal conductivity. Fourier's law.

Thermal shock.

Solidification phases: nucleation and growth.

Steel cooling. Martensitic transformations. Return: martempering and austempering.

Temper and hardness. Jominy essay. Hardening by precipitation and bitterness. Annealing. Recrystallization temperature.

Crystallization of vitroceramics. Sintering.

Related activities

Exercise resolution.

Second partial test.

Laboratory practice.

 

5. Electrical properties. Semiconductors.

Description

Electrical conductivity. Ohm's law. Resistance and resistivity. Variation with temperature and with the composition of an alloy.

Energy bands: valence and conduction. Fermi level.

Thermocouples.

superconductors

Insulators. Dielectric permittivity.

Intrinsic and extrinsic semiconductors. Electrons and holes. Doping pi n.

Semiconductor devices.

Related activities

Exercise resolution.

Second partial test.

 

Learning activities


1. First partial test (contents 1 and 2). [CE9, RA1, CB1, CB5]

General description

Written test to evaluate the contents developed in the first half of the course.

Support material

Statement of the test.

Deliverable and links to the evaluation

Test resolution.

The grade will represent 40% of the course grade.

Specific objectives

Explain theoretical concepts corresponding to topics 1 and 2.

Solve exercises corresponding to topics 1 and 2.

 

2. Second partial test (contents 3, 4 and 5). [CE9, RA1, CB1, CB5]

General description

Written test to evaluate the contents developed in the second half of the course.

Support material

Statement of the test.

Deliverable and links to the evaluation

Test resolution.

The grade will represent 40% of the course grade.

Specific objectives

Explain theoretical concepts corresponding to topics 3, 4 and 5.

Solve exercises corresponding to topics 3, 4 and 5.

 

3. Resolution of exercises (contents 1 to 5). [CE9, RA1, CB1, CB5]

General description

Some of the proposed exercises will have to be solved.

Support material

Collection of exercises.

Notes, books and other supporting material.

Deliverable and links to the evaluation

Generally these exercises will have to be solved outside the classroom. Some of them will be solved by the students in the classroom, collaboratively in groups of two or three students, and displayed on the board.

This activity will not directly contribute to the course grade. However, its realization will be very useful for the preparation of the written tests.

Specific objectives

Solve exercises related to the contents of the subject.

 

4. Practice 1. Metallography. [CE9, RA1, RA2, RA9, RA11]

General description

Demonstrative practice where the operation of a metallographic microscope is taught and images of the granular structure of various metals and alloys are acquired.

Support material

Practice script. Introductory presentation on metallography. Images obtained with a microscope.

Deliverable and links to the evaluation

Students, in groups of three, apply the ASTM standards for calculating grain size number and grain diameter. They also calculate the percentage of graphite in a nodular smelter. They deliver a written report with the calculations.

The overall grade for all internships represents 20% of the course grade. Some of the contents of the practices can also come out in the individual written exams.

Specific objectives

Perform numerical calculations with the appropriate units according to a material testing standard.

 

5. Practice 2. Tensile tests. [CE9, RA1, RA2, RA9, RA11]

General description

Students use a 1500 kg traction machine to break several metal test tubes and obtain the numerical files with the force and elongation data.

Support material

Practice script. Files with the strength and elongation data of each material.

Deliverable and links to the evaluation

Students, in groups of three, represent the stress-strain graphs with a spreadsheet (Excel), using force and elongation data and measurements of test tube dimensions. From the stress-strain graphs determine for each material the Young's modulus, elastic limit, maximum tensile strength and ductility. They deliver a report with graphs and calculations.

The overall grade for all internships represents 20% of the course grade. Some of the contents of the practices can also come out in the individual written exams.

Specific objectives

Understand the relationship between stress and strain in metals.

Use a spreadsheet to get graphs and perform calculations.

 

6. Practice 3. Hardness tests. [CE9, RA1, RA2, RA9, RA11]

General description

Demonstrative practice of measuring Brinell, Rockwell and Shore hardness.

Support material

Practice script.

Deliverable and links to the evaluation

Calculation of the Brinell hardness formula from the signal diameters to various metal samples.

The overall grade for all internships represents 20% of the course grade. Some of the contents of the practices can also come out in the individual written exams.

Specific objectives

Know different hardness scales.

 

7. Practice 4. Impact tests. [CE9, RA1, RA2, RA9, RA11]

General description

Demonstrative practice of Charpy and Izod impact tests on polymers, according to ISO 179 and 180 standards.

Support material

Practice script.

Deliverable and links to the evaluation

Students, in groups of three, calculate the energy absorbed by the samples in the impact rupture, taking into account the friction losses of the machine and assessing the effect of the sample temperature. They deliver a written report with the calculations.

The overall grade for all internships represents 20% of the course grade. Some of the contents of the practices can also come out in the individual written exams.

Specific objectives

Perform numerical calculations with the appropriate units according to a material testing standard.

 

8. Practice 5. Properties of Plexiglas and other polymers. [CE9, RA1, RA2, RA3, RA9]

General description

Demonstrative practice where a 5000 kg traction machine is used to break various samples of Plexiglas and other polymers, according to ISO 527. Density is also measured, with an adaptation of ISO 1183.

Support material

Practice script. Plexiglas manufacturer's data sheet.

Deliverable and links to the evaluation

Students assess whether the sample provided is from the Plexiglas described on the data sheet or from a substitute. They deliver a written report with the findings.

The overall grade for all internships represents 20% of the course grade. Some of the contents of the practices can also come out in the individual written exams.

Specific objectives

Perform numerical calculations with the appropriate units according to a material testing standard.

 

9. Practice 6. Thermal properties. [CE9, LO1, LO9, LO11]

General description

Students measure the heat capacity and thermal conductivity of various metals.

Support material

Practice script.

Deliverable and links to the evaluation

Students, in groups of three, submit a written report with the requested calculations, graphs, and conclusions.

The overall grade for all internships represents 20% of the course grade. Some of the contents of the practices can also come out in the individual written exams.

Specific objectives

Use a spreadsheet to get graphs and perform calculations.

Evaluation system


The final grade will be the weighted average of the grades of the assessable activities:

First partial test: 40%

Second partial test: 40%

Laboratory practices: 20%

Recovery exam: 80%

There will be a first partial test in the middle of the course, corresponding to topics 1 and 2, and a second partial test at the end of the course, corresponding to topics 3, 4 and 5.

For students who do not pass the assessment during the course, 20% of the internship grade will be maintained, and an overall retake exam will be held which will be worth 80% of the grade.

The resit exam may be used to pass the subject with a final grade of 5, but not to obtain a grade higher than 5.

In the event that the health regulations prevent a first face-to-face examination, the weighting of the evaluable activities will be:

Face-to-face final test: 70%

Laboratory practices: 30%

REFERENCES


Basic

Callister, WD Introduction to Materials Science and Engineering. 1a. edition. Barcelona: Reverté, 2007. ISBN 9788429172539 - 9788429172546.

Shackelford, JF Introduction to materials science for engineers. 6a. edition. Madrid: Pearson - Prentice Hall, 2008. ISBN 9788420544519.

Smith, WF, Hashemi, J. Fundamentals of materials science and engineering. 4a. edition. Madrid: McGraw-Hill, 2006. ISBN 9701056388.

Complementary

Gil, FJ Engineering materials. Problems solved. Barcelona: UPC, 2000. ISBN 9788483014110.

Cembrero, J. Materials science and technology. Problems and issues. Madrid: Pearson - Prentice Hall, 2005. ISBN 9788420542492.

Askeland, D. Materials science and engineering. Madrid: Thomson - Paraninfo, 2001. ISBN 8497320166.

Mangonon, PL Materials Science. Selection and design. Madrid: Pearson - Prentice Hall, 2002. ISBN 9789702600275.

Ashby, M., Jones, DRH Engineering materials. 1a. edition. Barcelona: Reverté, 2010. ISBN 9788429172553 -9788429172560.