Quiz 2 Flashcards
Major Design Materials
- Natural / Organics (Wood)
- Glass
- Metals
Properties of Wood
- Inexpensive, renewable, easily machined
- Light, strong, tough
- Can be moulded to complex shapes
- Warm in colour and touch
Soda Lime Glass Properties
- Low melting point
- easy to blow and mould
- Is cheap
Corning Gorilla Glass
- Made with intense temperature, special trough, robots, and molten salt bath
Metal’s Properties
- Composed on atoms of the same type
Two types of Metals
Ferrous and Non Ferous
What are Metal Alloys
Used in design and engineering applications and made of 2 + chemical elements of which one is metal
Ferrous Metals
Contain irons and have small amounts of other metals or other elements added. They are magnetic and have little resistance to corrosion
Examples of Ferrous Metals
Mild Steel
High Speed Steel
Stainless Steel
High Tensile Steel
High Carbon Steel
Cast Iron
Types of Iron Forms
Cast or Wrought Forms
Cast Iron Features
Resistant to destruction and weakening by oxidation
Uses of Cast Iron
Pipes, Machines, and Car Parts
Wrought Iron Features
Worked by hand, malleable iron
Features of High Carbon Steel
Contains 0.7 - 1.5% carbon
4 Groups of Steel
Carbon, Alloy, Stainless, Tool
What is Stainless Steel
Has 10-20% chromium as the main alloying element and values for high corrosion resistance.
What is Tool Steel
Has tungsten, molybdenum, cobalt, and vanadium in varying amounts to increase heat resistance and durability for cutting and drilling equipment.
What is Case Hardening Metals
Also known as surface hardening where the surface of a metal object is hardened while the metal underneath is soft
What are Non Ferrous Metals
Metals with no iron, not magnetic and more resistant to corrosion. Good metal conductors
Types of Non Ferrous Metals
Aluminium, copper, lead, zinc, and tin
Features of Aluminium
Primed with Zinc Chromate to be used on aircraft
BC Ferries Controversy
Made with aluminium hulls and superstructures to be lighter, faster, and more fuel efficient but needed special welding techniques causing cost overruns and manufacturing delays
Features of Magnesium
Low density, high mechanical strength and dampening capacity. Welds easily and can be plated or painted to prevent corrosion, but can be burned when overheated
Features of Tin
Low melting point, easily alloyed with copper, zinc, and lead. Used in solders but is weak for mechanical applications
Features of Zinc Alloy
Used in numerous applications from car components or hardware products. Moderate strength and ductility
What happens when you put a force on structures
It deforms depending on the compressive force
4 Mechanical Properties of Metals
- Ductility
- Compression
- Hardness
- Brittleness
What is Ductility
The abilities of a material to withstand plastic deformation without rupture
What is Compression
A measure of the extent to which a materials deforms prior to rupture
What is Hardness
The ability of a material to withstand penetration and scratching
What is Brittleness
Opposite of ductility and can brittle easily
Types of Forces that Act on Structures
Compression, tension, torsion, shear and bending
What is stress
The measure of the internal forces acting within a deformable body
What is Torsion
Also known as Twisting
What is Bending
The behaviour of a structural element subjected to an external load applied perpendicularly to a longitudinal axis of an element
What is Shearing
When items on the top when bent will appear longer than the ones on the bottom due to a shorter diameter on the inside versus outside
What is Triangulation
Using diagonal struts or angle brackets to strengthen intersections
Where are structures at their weakest
At their intersections
Three types of Joining Metal
Thermo, Adhesives, Mechanical
What are Adhesives
Joining thin materials and invisible joints, often used for load bearing applications
Types of Thermo Metal Joining
Soldering, Brazing, Gas Welding, Arc Welding, Spot Seam, Laser Beam Welding
What is Soldering
Primarily for conducting electric current. Join metals together using temperatures below 850 F where the solder cools to bond the parts together
Considerations for Soldering
Has little strength so it needs to support a load. Is best used when stress isn’t a factor
Type of solder alloys
Tin lead, tin silver, zinc aluminium
What is Brazing
Similar to soldering but done at temperatures above 850. Stronger than soldering because limited alloying occurs between the filler metal and the base metals
What is Gas Welding
No filler needed, metal parts are heated above melting to flow together
What is Arc Welding
Type of welding that uses a power supply to create an electric arc to melt the metals
What is Spot Seam
Rapid economical and simple process for sheet metal fabrication where the sheets are clamped between two electrodes that conduct a measured current
What is Laser Beam Welding
a Focused, high powered light beam is directed, shaped and focused precisely on the work piece
Types of Mechanical Fasteners
Threaded, Special Purpose, Nonthreaded
2 Types of Threaded Fasteners
Mechanical Fasteners and Threaded Fasteners
What are Mechanical Fasteners
Using screws to fasten assemblies together
What are Threaded Fasteners
When a metal is too soft, use a thread insert which is drilled and tapped to accept a machine screw
Types of Finishing Plastics to Add Artwork
- Heat Transfer
- Hydro Printing
- Decals
- Patterns
What is Heat Transfer
Artwork is transferred to fabric from film that is placed between the product and the heat press without messy inks. Clean and environmentally safe and needs a flat surface
What is Hydro Printing
Used on metal, plastic, glass, hard woods, various materials to apply onto curved 3D objects via a floating ink layer in a vat of water
What is Decal
Pigmented decorations is printed on pre cut transparent with adhesive backing
Other types of finishing plastics
- Flocking and Suede Flocking
- Finishes`
What is Flocking
Placing a soft touch or finish on resin parts where fibres are adhered to the part surface, followed by electrical charge to make the fibres stand
Types of Finishes
Metallisation,Electroplating
What is Sputtering
A bright durable metallic finish with abrasion resistance
What is Deburring
Razor like thin triangular ridges created when a sheet is sheared, cast, or forged
Types of Deburring Metal Parts
- Grinding Fluids
- Polishing
- Shot/Sandblasting`
Types of Chemical Metal Finishing
- Electroplating
- Electropolishing
- Anodic Coating or Anodising
- Vacuum Metalling
- Porcelain Enamel
- Flame Spraying
What is Electroplating
Coating of an electrically conductive object with a layer of metal using electrical currents
What is Electropolishing
Can produce mirror like surfaces because there is no mechanical contact with the work piece
What is Anodic Coating
Oxidation process that converts the surface of aluminium and magnesium to an oxide layer, providing a finish/protection
What is Vacuum Metallising
Plating metal is evaporated at high temperatures in a vacuum and deposited on the part. Provides a uniform coating on complex parts
What is Porcelain Enamel
Acts as a protective surface for cooking utensils, kitchen and bathroom fixtures. High temperature and acid resistant
What is Flame Spraying
Coating processes in which melted materials are sprayed onto a surface
