The capacity of a metal to be hammered into sheets.
Rated on a relative scale; non-numeric.
Not malleable - cast iron
Super malleable - gold
The capacity of a metal to be drawn (pulled) through a die, to produce wire.
Metal is typically plasticized by heating, but not molten.
Some metals are cold drawn (drawn at room temperature)
Rated on a relative scale; non-numeric
Not ductile - cast iron
Super ductile - aluminum, copper, mild steel
A hardened surface (often high strength metal) having a precisely shaped, precisely dimensioned opening through which ductile metals are drawn (pulled) to produce wire.
Pushing (pressing) a heated, plasticized, though NOT molten, metal through a precisely shaped, precisely dimensioned opening in a die.
Suitable for producing:
-detailed, complex shapes
-long continuous members of a given shape/profile
Most extrudable metal - aluminum
Not extrudable metal - ferrous metals
Pounding a heated, plasticized, though NOT molten metal into shape, to produce a member or component.
Classical image of blacksmith pounding heated metal on an anvil = forging
It increases toughness of ferrous metals
Steel and wrought iron forged while RED HOT
Toughness, Fatigue Resistance
The capacity of a metal to withstand repeated deformation without failure/breaking.
A change in the molecular structure of a metal as the result of repeated deformation.
Results in loss of toughness and creating brittle failure of the metal.
Use of a mechanical hammer and often repetitive blows to force a heated plasticized (NOT MOLTEN) metal into a precisely dimensioned die having the shape of the member to be produced.
Precisely dimensioned steel members (quality wrenches and architectural hardware) are often produced by DROP FORGING.
Pouring molten metal into a mold having the shape/profile/dimension of the member to be created.
Suitable for use with nearly ALL metals.
Does NOTHING to increase strength of metal.
Use of injection process, blow molding techniques, or hydraulic pressure to force molten metals into all the crevices of a shaped mold.
Suitable for very precise/intricately detailed shapes.
Reducing heated, plasticized (not molten) member to final profile and dimension by repeatedly passing th emetal through a series of rollers which incrementally squeeze the metal with each pass through the rollers.
Structural steel and structural aluminum shapes most commonly produced this way
Rolling metal to shape/profile at room temperature
Increases toughness, tensile strength.
Used for some structural metal decking material and light gauge steel
Squeezing sheet metal between matching pairs of metal dies, to produce a desired shape/profile, or texture.
Metal siding and roofing products, metal decking are produced this way.
Folding sheet metal in a device (brake) designed specifically for the purpose.
Most common method for producing flashings (waterproofing) of all kinds, as well as square and rectangular duct-work.
Heat Treated/hardened steel
Quenching - when heated red-hot then plunged quickly into cold water.
Steel becomes much harder, also more brittle
Steel heated to moderate temperature (below red hot) then cooled slowly.
Steel becomes harder, stronger in compression and tension, tougher, much less brittle.
Steel heated to very high temperature, then cooled very slowly at a carefully controlled rate.
Steel becomes tougher, much softer, easier to work, much less brittle
It also reduces internal stresses
Performing forming operations at room temperature.
Steel is often hammered, rolled, or drawn.
Tensile strength greatly increased. (good)
Brittleness increased. (bad)
Use of a rotating cutting wheel to cut metal from the work piece.
Capable of very precise tolerances, intricate shapes, precise dimensional control.
Rotating the work piece and cutting material from the rotating stock.
Very precise dimensional control.
Producing Screw/Bolt/Nut Threads
Tap: produces threads in a hole
Die: produces threads on a solid rod or hollow tube or pipe
Fusion process, filler metal used.
Steel and aluminum commonly welded.
High heat form an electric arc (or a gas flame) melts metal to be connected, on both sides of joint; additional metal, from rod or wire or consumable electrode, is also molten, flowed into joint; fusion process, all metals fuse together at joints. THE END.
Shielded arc process required: MIG, TIG, or Heliarc.
Not a fusion process; joint not as strong as metals being connected.
Metals to be joined heated, usually by gas flame, not molten. Brass with its low melting point is molten, flowed into joint at connection. Molten brass adheres to heated metal at join, bridges gap at joint.
Non-fusion process for joining metals.
Lead or lead/tin alloy is melted into the heated joint and bonds to the pieces it joins.
Low strength provided at the connection.
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