Lecture

Electrical Resistivity in Metallic Systems

Graph Chat

Chat with Graph Search

Ask any question about EPFL courses, lectures, exercises, research, news, etc. or try the example questions below.

DISCLAIMER: The Graph Chatbot is not programmed to provide explicit or categorical answers to your questions. Rather, it transforms your questions into API requests that are distributed across the various IT services officially administered by EPFL. Its purpose is solely to collect and recommend relevant references to content that you can explore to help you answer your questions.

Description

This lecture explores how electrical resistivity measurements can characterize microstructural features of metallic systems. It covers examples such as monitoring precipitation kinetics in an aluminum-silver alloy and observing ordering phenomena. Additionally, it discusses evaluating solid solubility evolution with temperature in a silver-silicon system, highlighting the importance of electrical resistivity measurements in determining solid solubilities in metals and validating composite theory.

Official source

Related concepts (28)

Phase diagram

A phase diagram in physical chemistry, engineering, mineralogy, and materials science is a type of chart used to show conditions (pressure, temperature, volume, etc.) at which thermodynamically distinct phases (such as solid, liquid or gaseous states) occur and coexist at equilibrium. Common components of a phase diagram are lines of equilibrium or phase boundaries, which refer to lines that mark conditions under which multiple phases can coexist at equilibrium. Phase transitions occur along lines of equilibrium.

Alloy

An alloy is a mixture of chemical elements of which at least one is a metal. Unlike chemical compounds with metallic bases, an alloy will retain all the properties of a metal in the resulting material, such as electrical conductivity, ductility, opacity, and luster, but may have properties that differ from those of the pure metals, such as increased strength or hardness. In some cases, an alloy may reduce the overall cost of the material while preserving important properties.

Solubility

In chemistry, solubility is the ability of a substance, the solute, to form a solution with another substance, the solvent. Insolubility is the opposite property, the inability of the solute to form such a solution. The extent of the solubility of a substance in a specific solvent is generally measured as the concentration of the solute in a saturated solution, one in which no more solute can be dissolved. At this point, the two substances are said to be at the solubility equilibrium.

Microstructure

Microstructure is the very small scale structure of a material, defined as the structure of a prepared surface of material as revealed by an optical microscope above 25× magnification. The microstructure of a material (such as metals, polymers, ceramics or composites) can strongly influence physical properties such as strength, toughness, ductility, hardness, corrosion resistance, high/low temperature behaviour or wear resistance. These properties in turn govern the application of these materials in industrial practice.

Metallography

Metallography is the study of the physical structure and components of metals, by using microscopy. Ceramic and polymeric materials may also be prepared using metallographic techniques, hence the terms ceramography, plastography and, collectively, materialography. The surface of a metallographic specimen is prepared by various methods of grinding, polishing, and etching. After preparation, it is often analyzed using optical or electron microscopy. Using only metallographic techniques, a skilled technician can identify alloys and predict material properties.

Related lectures (47)

Metals and Alloys: Microstructures and Transformations

Explores metals and alloys, focusing on microstructures, transformations, energy footprints, and extraction processes.

High Entropy Alloys: Overview and Properties

Covers the definitions, stability criteria, classes, and influences on physical properties of high entropy alloys.

Metallurgical Processes: Hardening and Maturation

Explores metallurgical hardening processes and microstructure evolution in metals and alloys through heat treatment.

Metallic glasses: Formation and Properties

Covers the formation, properties, and behavior of metallic glasses, including the importance of rapid cooling and the mechanical properties of these unique materials.

Phase Diagrams: Solid Solutions and Phase Transitions