Metals

Metals

are a crucial element of our existence.

118, 92

The periodic table of elements consist of _______ elements, of which ____ are metals.

IRON, COBALT, NICKEL, iron triad

These are frequently used in electrical engineering apparatus due to their magnetic quality. Transformers, Inductors, Electromagnets, Magnetic Cores, as well as other applications, utilize these metal elements.

COPPER, SILVER, GOLD, coinage metals

Due to the eye-catching physical property of coinage metals, these are frequently used for aesthetic purposes.

PROTECTIVE ELEMENTS ZINC, CADMIUM, MERCURY

_____________ are used for various practices to limit the contact for other metal element that could possibly affect human health. (give three elements)

FACE CENTERED CUBE 74 BODY CENTERED CUBE 68 HEXAGONAL CLOSE PACKED 74

STRUCTURE OF METAL
____________, PF = ___%
______________, PF = ___%
________________________, PF = ___%

Valency

_____________ - Metals typically have 1 to 3 electrons in the outermost shell of their atoms

Conduction, Silver Copper, Lead

_______________ - Metals are good conductors because they have free electrons. ______ and ______ are the two best conductors of heat and electricity. ______ is the poorest conductor of heat.

LUSTER

______________ - Metals have the quality of reflecting light from their surface and can be polished e.g., gold, silver and copper.

MALLEABILITY

___________________ - Metals have the ability to withstand hammering and can be made into thin sheets known as foils.

DUCTILITY

______________ - Metals can be drawn into wires.

HARDNESS, sodium potassium

_____________ - All metals are hard except __________ and _____________, which are soft and can be cut with a knife.

DENSITY, Iridium osmium, lithium

_________________ - Metals have high ___________ and are very heavy. ____________ and ___________ have the highest _____________. whereas __________ has the lowest ________.

MELTING AND BOILING POINT, tungsten, mercury

Metals have high _____________. ___________ has the highest ______________ whereas ___________ has the lowest.

STATE, mercury

_______________ - Metals are solids at room temperature with the exception of ___________, which is liquid at room temperature.

MERRY JOY TRUPA

Finishes 2nd in the Standard Distance Duathlon in the 2023 PTO Asian Open in Singapore

Reigning Powerman Malaysia Champion

Metal forming

_____________ is a process where materials are subjected to plastic deformation to obtain the required size, shape, and/or change the physical and chemical properties. 

Casting, Deformation, Material Removal

Metal Manufacturing Processes

Casting Processes

molten metal is poured into a mold, allowed to cool, and solidify, and then the item is removed.

Expendable Mold Casting

the part needs to be removed after the mold has been destroyed.

Permanent Mold Casting

wherein a ductile material is employed to create the mold, which can be used repeatedly.

Powder metallurgy

- A metal powder is compressed into the appropriate shape and heated to cause the particles to join into a hard mass.

Deformation Processes

• These processes use plastic deformation resulting from the use of a tool that applies stresses to the piece which exceed the yield stress of the metal.

• it changes the shape of solid materials.

BULK PROCESSES

• It is characterized by large deformations and shape changes and by the fact that the surface area to volume ratio is relatively small.

• are distinguished by significant shape and deformation variations, as well as by a relatively low surface area to volume ratio.

SHEET METALWORKING

• Is a manufacturing process of cutting and forming relatively thin metal sheets, strips, and coils to create desired shape sheet metal parts.

MATERIAL REMOVAL PROCESSES

These processes remove extra material from the workpiece in order to achieve the desired shape.

MACHINING OPERATION

These are cutting operations using cutting tools that are harder than the metal of the product.

ABRASIVE MACHINING

In these methods material is removed by abrasive particles that normally form a bonded wheel.

NONTRADITIONAL PROCESSES

These methods use lasers, electron beams, chemical erosion, electric discharge and electrochemical energy instead of traditional cutting and grinding tools.

Hardness Testing

- is a non-destructive test technique that includes indenting a metal surface under controlled conditions by delivering a steady stress via a rounded or pointed item.

Brinell

Uses a carbide ball indenter to measure hardness on course or uneven materials.

Vickers and Knoop

Uses a light load to test hardness indentations in a range of materials.

Rockwell

Measures the depth of penetration on soft or hard metal materials.

Tensile Testing

- To calculate many mechanical parameters, the test entails loading a sample with a well-defined shape along the axis in tension, typically until it fractures.

Proportional Limit

- It is the part of the stress-strain curve when Hooke's law is followed. The stress-strain ratio provides us with a proportionality constant known as Young's modulus in this limit.

Elastic Limit

- The material returns to its previous location up to that point on the graph when the load acting on it is totally removed. Beyond this point, the material is unable to return to its initial position and begins to exhibit plastic deformation.

Yield Point

- The point at which a material begins to deform plastically is known as the ____________. __________ is passed, and then there is permanent plastic deformation.

Ultimate Stress Point

- It is a point that symbolizes the highest stress a material can withstand before failing. Beyond this, failure happens.

Breaking Point

- The failure of the material occurs at this point on the stress-strain curve.

Ferrous Metals, Non-Ferrous Metals

Two Types of Metal Alloys

FERROUS METALS

ARE ALLOYS PRIMARILY COMPOSED OF IRON WITH VARYING AMOUNTS OF CARBON AND OTHER ELEMENTS.

Steel, Cast Iron

Two Types of Ferrous Metals

Plain Carbon Steel, Alloy Steel

Two Types of Steel

Plain Carbon Steel

_______________ primarily consists of iron and carbon, with small amounts of other elements that do not significantly alter its mechanical properties.

low, medium, high carbon steel

Three Types of Plain Carbon Steel

tool steel, stainless steel

Two types of alloy steel

LOW CARBON STEEL

Contains less than about 0.25 wt.%C (Mild steel)

• High tensile strength, Ductile, and quite tough.

• Poor resistance to corrosion.

• Used for wires, bolts and pipes

ALLOY STEEL

• Made of iron, carbon, and other elements such as silicon, nickel, chromium, and etc.

• on the other hand, incorporates various alloying elements in addition to iron and carbon, which significantly modify its mechanical properties.

grey cast iron, white cast iron, malleable cast iron

Three Types of Cast Iron

NON-FERROUS METALS

_____________________ are alloys or metals that do not contain any appreciable amounts of iron.

iron, ferrite, ferrum, iron

All pure metal are non-ferrous elements, except ____________, which is also called _____________ from the Latin ‘___________,’ meaning “_____”.

Collection, Sorting, Processing, Shredding, Melting, Purification, Solidifying

Metal Recycling process

Materials Science

• Investigate relationship between structures and properties of materials.

Material engineering

• Create product from existing materials.

• Develop materials processing techniques.

Structure of materials, properties of materials, processing of materials, performance of materials

Materials Science and Engineering has four components

Mechanical, electrical, thermal, magnetic, optical, deteriorative

Six categories of proerties

Stress

A quantity that describes the distribution of internal forces

Strain

Deformation of the materials die to stress

Material Strength

Is a measure of the stress a material can withstand w/o bending, breaking, or deforming

Ultimate strength

Maximum stress

Yield strength

Starts to deform plastically.

Ductility

Ability of a material plastically under tensile stress

Brittleness

Property of a material to fracture at low values of strain.

Toughness

To absorb energy up to fracture

Resilience

Ability to bounceback

Hardness

To resist penetration

Fatigue

Is a material property thst determine its behavior when subjected to repetitive or cyclic application of load.

Crack formation, crack growth, failure

Stages of fatigue failure

Creep

Slow and progessive deformation of a materials.