![]() It can be worked (or 'wrought') just like softer iron, and it will keep a finer edge, capable of being honed to sharpness. This process hardens the metal and the effect is considerably greater if the hot metal is rapidly reduced in temperature, usually achieved by quenching it in water. If iron (Fe) is reheated in a furnace with charcoal (containing carbon), some of the carbon is transferred to the iron. ![]() The use of iron (Fe) is maintained in weaponry until about 1100 BC when the discovery of Steel came about again probably by accident. The Iron Age (1500 BC) started once the ability to smelt the metal (which has a much higher melting point: 2,800☏ (1,538☌)) became available. ![]() The next metal to come into use was Iron (Fe). Smelting of copper and later bronze started around 3000 BC. The discovery that they made a harder metal was probably just a fortuitous accident but ushered in a higher level of industry in early civilizations. When these two metals are combined they create a stronger metal: Bronze. Bronze is an alloy of two metals: Copper (Cu) and Tin (Sn). Immediately following the Age of Copper(Cu) is the Bronze Age (2800 BC). The Age of Copper is defined as such because we note that Neanderthals at the time were hammering copper into crude knives and farming instruments. So the smaller the grains the less malleable (stronger) the metal becomes.Įarly man discovered the process of "working" metal to form weapons as far back as 7000 BC. This hardness comes about because the metal atoms are no longer aligned so that they can easily slide across each other, the areas of irregular patterning prevent it. The faster the cooling process the smaller the grains that form and the harder the metal becomes. Grain size can be controlled by the time in which the metal is allowed to cool. Grains can be large or small depending on the process by which they were formed. Grains are regions of irregular structure that exist in the overall crystalline structure of the metal. However, during solidification of a molten metal or recovery from a stressor like beating different regions are forced to crystallize at the same time. The atoms in a metallic solid are arranged in close packed crystalline arrangements as shown above. This is because of the Metallic Microstructure. Smelting or physically beating a metal causes the metal to become stronger. There are three main types of packing in the transition metals: Face-Centred Cubic (FCC), Body-Centred Cubic (BCC) and Hexagonal Close Packed (HCP). This gives metals their ability to conduct heat and electricity well. The nuclei (represented as spheres) are arranged into fixed orientations while the electrons are free to flow around them. Metal atoms are arranged around each other into what is called a cubic cell (shown above). This property of metallic structure comes from their atomic structure: If you beat the metal harder, the layers remain in their new orientation: If the stress is released again, they will fall back to their original positions: If a small stress is put onto the metal, the layers of atoms will start to roll over each other. The properties of malleability and ductility comes from the ability of the atoms in the metal to roll over each other into new positions without breaking the metallic bonds that hold them together. But metals are also hard which means once formed into a shape by smelting (liquefying using heat) or beating, the shape is maintained. Metals can therefore be shaped into almost any form needed. For example, copper can be made into thin sheets and wire because it is both malleable and ductile. A ductile material is one that can be pulled out, or drawn, into a long wire. A malleable (mal ee uh bul) material is one that can be hammered or rolled into flat sheets and other shapes. The physical properties of metals include shininess, malleability, ductility, and conductivity. So what is a metal and what makes it so useful for the creation of weapons? Metal Both guns and knives and other bladed instruments are almost always composed of metal. The material that composes most weapons is metal.
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