Earlier, I had stated that we would cover various topics regarding maintenance steel. One of the topics listed was regarding Magnetic and Magnetism. Are those words synonyms? They are not, although you might think they were if you have been working in customer support for any length of time. It is within the framework of customer support that the discussion ensues. Many people get the two confused.

A customer might say; “I must have a grade that is non-magnetic, when they mean “not-magnetized”. Or just the opposite. Keep it simple when discussing this with a customer. This has always helped me;

“Magnetic – will attract a magnet”

“Magnetized – will attract another piece of steel”

Hundreds of years ago when I was just getting acquainted with some folks who had hot tempers, little patience, and misunderstood differences, I called many senior steel people for guidance. One particular person seemed to have a pretty good handle on the phenomenon of magnetism. His response still resonates.

“Well son. Magnetism is your worst nightmare. Whereas; “Magnetic”, is intrinsically neither good nor bad.”

Steels may pick up magnetism from many sources. It may occur at any place at any time. People who study these types of mysteries, like Sheldon Cooper, will surely have a more detailed explanation as to what causes magnetism in steel. But for me, when my new book comes out it will be titled; Metallurgical Principles as Defined by Ghosts and Magic. Fortunately, this is not a common occurrence. Some people have suggested that simply the direction you store the steel, as it relates to the points of a compass, may contribute to magnetism. Many times steel that is near an electric motor will become magnetized. Oxy (torch) cutting steel may induce magnetism.

We encountered steel bars stored in racks next to a main cut-off saw that started becoming magnetized. It was a nightmare for a while, and we had a difficult time with that problem. We studied the problem, made lots of calculations and moved the steel. Problem solved.

Back to the person who defined magnetism as my worst nightmare. I asked him about removing magnetism once encountered. Again, his sage advice sticks in my mind. “You can heat it, or you can beat it. Or you can degauss it. But, depending on how bad it is, there are no certainties that you will remove it.

Basically, if you encounter light magnetism on smaller diameter steel bars, you can set up a ringing vibration by lightly peening the bar end with a steel hammer. I have tried that and on occasion it mostly never works. It dawned on me, however, that many years ago you could get small horseshoe shaped steel magnets in the dime-store or in boxes of Cracker Jack. (ask your grandparents what a dime store was. You can ask them about Cracker Jack also). Anyway, if you had one it was  prized possession since other than hoops and sticks, toys weren’t invented yet.

Almost every time I had one, some kid would grab it and drop it. When it stuck to the ground; woops no more magnetism. Between the explanation about beating it (From Michael Jackson’s book, Principals of Metallurgy), and the horror, (the horror), of my persona experience, that tip stuck with me. I tried it and mostly it has never worked. But, as he said, on smaller bars, with light magnetism, it may work.

Now, where was I? Ok, “You can heat it.” You will have to look that one up and it will depend on the grade of steel. Sometimes, passing heat evenly along the bar moving from one end to the other will relieve the problem.

As far as de-gaussing goes, it seems to me if you already know the word you already know how to remove magnetism, or information from hard drives. It is basically employing reverse polarity to remove magnetism. There are machines that are made to do that specifically, or, some adept souls can accomplish it by using the leads from a portable welder.

An interesting fact about degaussing is that once you pass the wand (looks like a kids bubble blower, ask your grandmother) down the bar, you have to keep moving for about two feet past the end of the bar. We checked that with a gauss meter (Measures Magnetism), and it was very interesting.

The magnetism would be removed, (following the degaussing wand down the bar), but, if you didn’t keep going several feet off the end of the bar it snapped back to the bar.

So, if magnetism is mostly bad. Is magnetics steel always good? Not necessarily. There are applications that are disrupted by the use of steel that is magnetic. The point is that many people who find they are working in an industrial field that utilizes metals get the two conditions mixed up.

It is worth taking a moment to insure both parties are on the same page and that they truly want what they are asking for. Once you are discussing apples and apples, let them determine the needs of the applications. Remember, these posts are geared toward those of us who are not degreed engineers. Your customer, or vendor, is expected to know their field of endeavor. You attempting to tell them about the needs of their application will be covered in a book I will be writing later this year, entitled; The Joys of Liability in the Metals World.

-Howard Thomas, January 2nd 2018

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