Please enable JavaScript.

Coggle requires JavaScript to display documents.

Al (1) (Alloying (Purpose (Displace Al atoms in the crystal lattice, Add…

- - - - Si
      - Mg
      - Mn
      - Cu
      - Zn
    - - B
      - Cr
      - Zr
      - Pb
      - Ni
      - Ti
  - - - Major Alloying Elements
      - Mechanisms
        
        Strength Contribution
      - Heat/Non-Heat Treatable Alloys
        
        Obtain Strength
        
        Precipitation Hardening
        
        Alloying Elements in SS & Cold Deformation & Annealing
  - - - Properties
        
        Strong
        
        Corrosion Resistant
        
        High Cost
        
        Reduce Weldability
      - Applications
        
        Aircraft
        
        Aviation Alloy
    - - Reading
        
        Mg + Al (9%) + Zn (1%)
      - Light Metal Casting Alloy
      - Properties
        
        Low Density
        
        Good Ductility
        
        Good Machinability
  - - - Wrought Non Heat-Treatable Alloys
        
        Sheets & Bars
      - Wrought Heat Treatable Alloys
        
        Tubings & Forgings
      - Casting Non Heat-Treatable Alloys
        
        Mould Casting
      - Casting Heat Treatable Alloys
        
        Mould Casting
  - - - Precipitation (Ageing)
        
        Particles/Thin Bars
        
        Mg & Si
    - - Relationship
        
        Alloying Element Amount ~ Temp
      - Quenching : High Temp => RTP
        
        Alloying Elements cannot diffuse to form particles
        
        Al becomes oversaturated with Mg & Si in SS
    - - Process
        
        Step 1: Heat to ~180 °C for a few hours
        
        Step 2: Controlled Diffusion of Si & Mg atoms for Mg2Si precipitation
        
        Step 3: Deformation of surrounding crystal lattice as precipitates form
        
        Step 4: Hard Needles Precipitated
        
        Step 5: Dislocations require force to pass through
        
        Step 6: Material flow stress increases
        
        Step 7: Overaged
        
        Step 8: Flow Stress decreases
      - Overaged
        
        Particles grow & disappear
        
        Reduced lattice deformation
- - - - Hot Rolling
        
        Ingot reduces to final gauge for heavy plate/coils for cold rolling
  - - - From Unalloyed Al/MnMg Al
- - - - Heat Treatable Alloys
    - - Gravity
        
        Heat Treatable Alloys
      - Pressure
        
        Non Heat Treatable Alloys
- - - - Cold Forging
      - Impact Extrusion