Page 54 - CITS - WCS - Mechanical

WORKSHOP SCIENCE - CITS

Physical properties
• Density:
• Amount of mass contained in unit volume of material
• Higher the density the heavier is the substance
• For water 1000 Kg/m³
ρ = Mass
volume
• Unit:
Kg/m³
• Viscosity(dynamic viscosity): Property of fluid which offers resistance to the flow of one layer of fluid
over another adjacent layer of fluid
• Unit of viscosity : Ns/m²
• Kinematic viscosity, μ = Dynamic viscosity
ρ
• Unit:m²/s
• Specific gravity
• Ratio of density of a substance to the density of fresh water at 4°C
• S = Density of substance
Density of water
• No unit. For mercury 13.6
• Colour:
• Represents reflective properties of substance
• Colour of material is that colour which is reflected.Eg: Yellow colour of gold
• Porosity: Presence of small holes or vacant space
• Eg:Clay
• Melting point: Temperature at which material changes its state from solid to liquid at standard
atmospheric pressure

Types of Metal Composition Uses
Cast Iron Has more carbon than most other types, Cookware, small components subject
which relatively affordable due to lack of to wear such as, rods, gears, pins, and
other alloying elements outside of iron mining equipment.
carbon.
Carbon Steel Typically over 90% iron and the most Furniture, structure and automotive
frequently used ferrous metal. components.

Stainless Steel 100% recyclable usually a high amount Appliances, pharmaceutical and medical
of chromium which helps resist corrosion equipment, food-grade equipment, and
better than carbon steels. knives.

Engineering Steel Mostly iron, but amounts of copper, Tools, dies, and machining equipment.
vanadium, tungsten manganese, and
other elements can tailor it for toughness,
ductility, tensile strength, hardness, and
other properties.

Alloy steel is a type of steel alloyed with several elements such as manganese, nickel, chromium, molybdenum,
vanadium silicon and boron. These alloying elements are added to increase hardness, strength, wear resistance,
and toughness.

Uses of Alloys in Daily Life
• Manufacturing of kitchenware.
• Manufacturing of plumbing.

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CITS : WCS - Mechanical - Exercise 2 CITS : WCS - Mechanical - Exercise 2