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.

3J International is an expert in magnetic materials and magnetic products. Customers rely on us to ensure that all rules and regulations are being followed for shipping of magnetic products. All personnel responsible for shipping magnets by air are trained for that purpose as per Federal Aviation Authority (FAA) requirements.

Magnets and magnetized products are considered “Miscellaneous Dangerous Goods” according to the International Air Transport Association (IATA) and accordingly must follow the Dangerous Goods Regulations (DGR).

Neodymium (more precisely Neodymium-Iron-Boron) magnets are the strongest permanent magnets in the world.

No, both poles are equally strong.

Neodymium magnets are a member of the rare earth magnet family. They are called "rare earth" because neodymium is a member of the "rare earth" elements on the periodic table. Neodymium magnets are the strongest of the rare earth magnets and are the strongest permanent magnets in the world.