Elasticity

Ability to regain original shape after deformation. Lead is very malleable but has little elasticity—it does not spring back when bent.

Fusibility

Property of becoming liquid when heated. Different metals have different melting points.

Hardness

Resistance to deformation, bending and cutting.

Malleability

Capacity to be extended in all directions without fracturing by rolling, hammering or beating. Gold is the most malleable metal, and can be beaten into leaf 1/25000 in thick.

Tenacity or cohesion

Resistance to a pulling force—the opposite to ductility.

Work-hardening

Hardening of metal while it is being hammered or bent. The hardening causes the metal to become more brittle, and it must therefore be annealed to prevent it from cracking.

PROCESSES IN WORKING METAL Annealing

Heating metal to restore it to its softest possible working state.

Extruding

Forcing malleable materials through holes to produce bars, sections or tubes.

Forging

Shaping hot metal by hammering.

Hardening

Producing maximum hardness in high carbon steel by heating it to bright cherry red, then quenching it in water or brine. This process makes metal brittle and is usually following by tempering.

Pressing

Forming sheet metal to shape with a press tool.

Spinning

A process in which a fast revolving sheet of ductile metal is forced over a wood or metal form. Much aluminium alloy kitchenware is produced in this way.

Tempering

Removing some of the brittleness from steel after it has been hardened. The tempering is done by heating the steel, then cooling it— temperatures and speed of cooling vary with the types of steel. Steel cannot be tempered without being hardened.

Bluing

Treating steel to improve its corrosion-resistance. The metal is heated to create an oxide skin, then quenched in oil.

Casting

Production of metal shapes by pouring molten metal into moulds.

Drawing

Pulling ductile metals through holes in a plate, to reduce their cross-sectional areas.

Woodworking Tools and Installation Tips

Woodworking Tools and Installation Tips

There are a lot of things that either needs to be repaired, or put together when youre a homeowner. If youre a new homeowner, and have just gotten out of apartment style living, you might want to take this list with you to the hardware store. From remolding jobs to putting together furniture you can use these 5 power tools to get your stuff together. Dont forget too that youll need a few extra tools for other jobs around the house.

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