Metal properties
Metal Properties
Basic Properties
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Density: Marks the mass of a metal per unit volume. High-density metals are heavy for their size, such as gold and platinum. Lower density metals like aluminium are lighter.
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Melting and boiling points: Metals generally have high melting and boiling points, but these vary widely amongst different types. Understanding these temperatures is crucial for successful forging and casting.
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Electrical conductivity: Metals are typically good conductors of electricity. Silver and copper are amongst the best, while stainless steel is relatively poor.
Physical Properties
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Malleability: Refers to the ability of a metal being deformed under compressive stress without breaking. Gold is a highly malleable metal.
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Ductility: The capacity of a metal to be drawn into a thin wire without rupturing. Copper and aluminium are examples of highly ductile metals.
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Hardness: Represents a metal’s resistance to permanent deformation or deep penetration. It can be enhanced through various heat treatments.
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Tensile strength: The amount of pull a metal can withstand before breaking. High strength metals, including some types of steel, can endure high degrees of tension.
Chemical Properties
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Reactivity: Some metals react quickly with oxygen, while others are slow to oxidise. Understanding a metal’s reactivity helps prevent unintended damage and aids in conservation efforts.
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Corrosion resistance: Measures a metal’s ability to resist oxidation and other forms of chemical wear. Stainless steel and aluminium are known for their corrosion resistance.
Thermal Properties
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Thermal conductivity: Metals are normally excellent conductors of heat. This property is vital for applications requiring rapid heat transfer, such as in cookware.
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Coefficient of expansion: This value details how much the size of a metal object will change as the temperature changes. This is vital to consider during the forging process to prevent cracking or warping.
Magnetic Properties
- Magnetism: Some metals such as iron, nickel and cobalt are attracted to magnets and can be magnetised themselves. Other metals like copper and gold are not magnetic.
Understanding these properties is integral to the successful selection and manipulation of materials in blacksmithing.