There are several simple methods that can be used to identify the strong magnet North and South poles of neodymium magnets. 1) The easiest way is to use another magnet that is already marked. The North pole of the marked magnet will be attracted to the South pole of the unmarked magnet.
2) If you take an even number of magnets and pinch a string in the middle of the stack and dangle the magnets so they can freely rotate on the string, the North pole of the magnets will eventually settle pointing North. This actually contradicts the "opposites attract" rule of magnetism, but the naming convention of the poles is a carry over from the old days when the poles were called the "North-seeking" and "South-seeking" poles. These were shortened over time to the "North" and "South" poles that we know them as.
3) If you have a compass handy, the end of the needle that normally points North will be attracted to the South pole of the neodymium magnet.
4) Use one of our Pole Identifier Devices.

The traditional way of visualizing magnetic fields is to place a magnet near a surface covered with iron filings.

Yes, we've posted Demagnetization Curves for our most common Neodymium magnet grades right here.

Because pull force values are tested under laboratory conditions, you probably won't achieve the same holding force under real world conditions. The effective pull force is reduced by uneven contact with the metal surface, pulling in a direction that is not perpendicular to the steel, attaching to metal that is thinner than ideal, surface coatings, and other factors.

Neodymium magnet test the magnet use the professional instrument, such as the pulling force mater, flux mater Gauss meter. AIM Magnet have this can ensure the high quality magnet to the customer.

Ferromagnetic materials are strongly attracted by a magnetic force. The elements iron (Fe), nickel (Ni), and cobalt (Co) are the most commonly available elements. Steel is ferromagnetic because it is an alloy of iron and other metals.

Neodymium magnet Magnetized thru thickness mean is the magnetic direction is thickness direction, We use the description "Magnetized thru thickness" to identify the locations of the poles on our block magnets. The thickness is always the last dimension listed for block magnets. If you take one of our block magnets and place it on a flat surface with the thickness dimension as the vertical dimension, the poles will be on the top and bottom of the magnet as it sits. .

Yes, two or more magnets stacked together will behave exactly like a single magnet of the combined size.

No, we don't, nor does anyone else, because they don't exist. All Neodymium magnets must have at least two poles.

You definitely cannot solder or weld to neodymium magnets. The heat will demagnetize the magnet and could cause it to catch fire posing a safety risk.