How Does Ferrous Oxide Cause Joints To Lock Up

What are the different kinds of fasteners?

Nuts - Used with a bolt and washer to create a joint. It is considered a temporary joint because it can be easily removed.Bolts - Held on by a nut, typically with a shoulder, bolts have a much higher strength than screws and are used when removing the connection is likely.Washers - Used typically on the nut side of a nut and bolt assembly to provide the nut with a flat and smooth surface to fasten against. They can also protect the material surface.Screws - Used to hold materials together and considered permanent, screws hold themselves into the materials they are installed in without a nut.Rivets - Considered a permanent install, rivets hold materials together by expanding on one side of the hole resulting in a firm hold.Anchors - Typically permanent. Most are placed in a hole and somehow expanded to fill the hole and prevent pull-throughRetaining Rings - A ring the is either expanded or compressed and fit into a recess on a shaft. They are commonly used on shocks to hold springs under pressure.Dowel Pins - A cylindrical metal pin used in machinery to keep pieces in place.Security Screws - Serve the Same functionality as screws but with unusual head styles that may add extra security to your assemblyNote: There are many kinds of each fastener that can serve different purposes. For example sheet metal screws have sharp cutting threads that will easily cut through soft metals where as a wood screw is used primarily in wood to wood applications.

How can I make an iron nail rust faster? I've got two weeks to get it as rusty as possible and I am not allowed to use hydrogen peroxide stronger than 3%.

Store the nail under water and keep the water saturated with oxygen by bubbling air, but preferably oxygen, through the water to substantially accelerate oxidation to produce ferric oxide. Some hydrated ferric oxide will also form to give Fe2O3nH2O as well as FeO(OH) and Fe(OH)3 that is the commonly encountered rust that readily flakes off the oxidised iron.Because rusting involves an electrolytic process at the microscopic level you could further accelerate the process by adding a trace of a salt electrolyte, such as common salt or even ferrous as the the sulphate or chloride.The rougher the nail surface, the more microscopic anodes and cathodes are available for localised electrolytic oxidation. Therefore by etching the nail in an acid, prior to the oxygen bubbling treatment, the faster the rusting process will occur.

What is the difference between iron and steel?

Iron is an element however it is not found in its pure form and even then it only exists in the lab as it is very soft and very difficult to purify iron to its pure properties.Iron as the word is use commonly is typcially an alloy of iron with large amounts of carbon and also typcially manganese . Carbon content is typically 3-5% weight and maganese roughly .5-1.5% with other elements randomly present in smaller quantities. Silicon is typcially present in a couple weight percent in cast iron too.Irons main advantage is that is easier to cast than steel due to the low melting point the result of the high carbon content also reducing the carbon content to get steel then maintaining the higher temperature is expensive compared to iron.Steel however is much stronger and more ductile thus making it worth the effort to get the carbon out.A quick info about iron-carbonMetals and other solids can actually dissolve other elements into a solution . Iron does not dissolve carbon very well at low temp but it's solubility abruptly increases around 1000 C to .8 % increasing to almost 2.5% due to a change in the atomic arrangement . Carbon that doesn't dissolve turns into cementite which is an Intermettalic (basically a compound) that is very brittle but also strong. After 1-1.5% carbon steel becomes too brittle to be useful however 2% and up to 4% the melting point is rather low making it easy cast despite the brittle nature. At very high carbon percentages carbon will come out and become graphite making the cast iron ductile.Realistically high carbon steels and low carbon cast irons are similar . The reason for the different name is diminishing returns . Adding carbon to steel makes its harder and more brittle. At a point it becomes so brittle that any internal stresses or defects cause it to prematurely fail weakening the material. This occurs around 1.5-2% carbon. Materials around that concentration have the manufacturing disadvantages of steel with the low performance of cast irons thus don't really exist practically.

Why are copper metal wires used to conduct electricity?

Excellent answers, all. Really, on an engineering basis, aluminum and copper are the big competitors. Inside the house, copper is very much preferred. It is a better conductor and less subject to corrosion, oxidation and deterioration of properties when exposed to higher temperatures. It is about four times the cost of aluminum by weight, but for the limited amount of wiring inside of a house or small appliance, this is acceptable.  For cross-country transmission of power, however, aluminum is much less dense than copper. Hence, even though one must use more volume of aluminum to get the same conductivity, the weight of the cables is much less. Also, the cost of stringing all of the over-land transmission systems with copper would be staggering. (Copper is up quite a bit these days... spot price has been well over $3/lb for a week or two. Aluminum usually runs $0.90 to $1.00 / lb.)For sheer conductivity, however, silver is the king! That is why the electronics industry loves it. Often the critical factor affecting function is not determined by the long range over which one is transmitting an electric signal, but rather by the speed and quality of the connecting points. Hence, a tiny dab of silver (or gold) at those points can be extremely effective. Silver actually has conductivity better than gold, but gold is totally resistant to oxidation. Something even silver and copper cannot claim.