Introduction and Application of Non-ferrous Metals Nickel

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The content of nickel in the crust is not a small number, more than common metals lead, tin, etc., but obviously much less than iron. Besides, its melting point is pretty close to iron. Therefore, nickel is destined to be discovered later than iron. In the late 17th century, Europeans began to pay attention to the nickel arsenic mine. At that time, Germany was using it to manufacture cyan glass, mining workers called it kupfernickel. In German, “Kupfer” means “Copper”; “Nickel” is a bad language, meaning “deceptive guys”. So this word can be paraphrased as “counterfeit copper.” At that time people thought it was a mixture of copper and arsenic. Swedish chemist Cronstedt did a research about this minerals and obtained a small amount of metals different from coppers. In 1751 he published a research report, stating that this is a new metal, and called it nickel. This is also the origin of nickel’s Latin name niccolum and the symbol Ni. After nickel is discovered in Europe, the German first incorporated it into copper to make the so-called Germanic silver, or German silver, which is also known as China ‘s copper-nickel alloy.

The Basic Knowledge of Nickel

In nature, the main components of nickel miners are the nickeline (nickel arsenide) and gersdorffite (sulfur nickel arsenide). Cuba is the most famous country in the world that is rich in nickel mineral reserve. There are also plenty of nickel mine in Dominica.

Nickel is mainly used in the electroplating industry. Nickel-plated goods is beautiful, clean, and corrosion resistance. The extremely fine nickel powder is usually used in the chemical industry as a catalyst. Nickel is used extensively for the manufacture of alloys. Addition of nickel in the steel can improve the mechanical strength. If the nickel content in the steel is increasing from 2.94% to 7.04%, the tensile strength will increase from 52.2kg would/mm2 to 72.8kg/mm3. Nickel steel is used to make the components which withstand high pressure, impact and reciprocating loading in the machine, such as turbine blades, crankshaft, and connecting rod. The nickel steel containing 36% nickel and 0.3-0.5% carbon is of very small expansion coefficient, almost without thermal expansion and contraction. So, it is used to manufacture a variety of precision machinery, precision gauges and so on. High nickel steel containing 46% nickel and 0.15% carbon is called “eka-platinum”. Due to the fact that its expansion coefficient is similar to the platinum and glass, this high-nickel steel can be welded to the glass. It is important in the production of light bulbs, can substitute for the platinum wire. Some sophisticated lens attachment is also made of this kind of eka-platinum steels. The lens made by it will not fall from the box due to thermal expansion and contraction. The alloy composed of 67.5% Ni, 16% iron, 15% chromium, and 1.5% manganese, is of great electric resistance and can be used to manufacture various rheostat and electric heaters.

Titanium nickel alloy has strong memory ability. It can still keep accuracy even after a fairly long period of time and millions of times of repetition. Due to its “memory” ability is to remember its original shape, people call it “shape memory alloys”. This alloy has a characteristic called transformation temperature. Above the transformation temperature, it has a structure; below the transformation temperature, it has another structure. Different structures, different performances. Take a kind of nickel-titanium memory alloy as an example, when it is above the transformation temperature, very hard and strong, and below this temperature, it is very soft, and vulnerable to cold processing. Thus, when we need it to remember a shape, we simply make it that shape, which is its “permanent memory” shape. When below the transformation temperature, because it is very soft, we can make arbitrary deformation within a considerable extent. And when you need to restore it to its original shape, heat until it is above the transformation temperature. Nickel is magnetic, and can be attracted to a magnet. The alloys made by cobalt, aluminum, and nickel have stronger magnetism. When it is attracted by the electromagnet, not only that it will be attracted, but it can also hold up the things that are of 60 times of its weight. In this way, you can use it to make an electromagnetic crane. The color of nickel hydroxide is brownish black, but the color of nickel oxide is grey black. Nickel oxide is commonly used to manufacture nickel-iron alkaline batteries. Dimethylglyoxime is commonly used to identify bivalent nickel ions. In ammoniacal solution, the nickel ion (Ni2+) and dimethylglyoxime generates bright red precipitate (Ni(dmgH)2).