Is it true that 95% of all metals used in construction contain some kind of un-alloyed iron? If so, then practically every kind of object that we think of as ‘metal‘ (aluminum is not really thought of as a ‘hard metal‘) is magnetic.So, my question is, what metal -used in construction and not something flimsy like aluminum- isn‘t magnetic?I‘m researching for a screenplay, so thanks for the help.
The answer is not as simple as you might think. The type of magnetism most people think of is known as ferromagnetism. It is the strongest type of magnetism, but by no means the only type. Metals showing ferromagnetism include, but are not limited to: Iron (ferro), Cobalt, Nickel, Gadolinium, and Dysprosium. These are some of the most common metals in existence, and I guarantee you that every single metal product you use in your every day life contains significant amounts of one or more of these metals. Past ferromagnetism you have diamagnetism, paramagnetism, ferrimagnetism, metamagnetism, and several variations on these. Every material in existence is affected by magnetism to some degree or another, but those that are barely affected at all are classified as non-magnetic. A few common non-magnetic metals are aluminum, tin, copper, and zinc. Many metals are coated in zinc in a process known as galvanization (not to be confused with galvanized rubber, which simply includes more sulfur). Aluminum is often used in aircraft manufacture for it's strength and light weight, as well as temperature resistance. Copper is used in modern piping, tin is hardly used for anything nowadays, though it has many non-magnetic alloys that are used extensively such as pewter and bronze. Many circuit components are also made of various alloys of non-magnetic metals, but I'm not sure if that's really useful for your research.
Not an easy question to answer. Many larger buildings have stainless-steel window frames and trim. Stainless steel is very weakly magnetic. Many buildings have aluminum window frames and trim. The building may be 95% iron by weight, but that's all internal invisible structural beams, usually covered by concrete for fire-proofing and extra strength. You may want to consider that magnetic fields have very limited range. The strength drops off as the cube of the distance, so anything over an inch or so away and there is negligible force. Mst motors and generators have gaps measured in thousandths of an inch.
