1) Affect machining by causing to cling to a component.
2) Interfere with electronic equipment such as a compass.
3) Create a condition known as arc blow in the welding process. Arc blow may cause the weld arc wonder or filler metal to be repelled from the weld.
4) Cause abrasive particles to cling to bearing or flying surfaces and increase wear.
Removal of a field may be accomplished in several ways. This random orientation of the magnetic domains can be achieved most effectively by heating the material above its curie temperature. The curie temperature for a low carbon steel is 770 C or 1390 F. When steel is heated above its curie temperature, it will become austenitic and loses its magnetic properties. When it is cooled backdown, it will go through a reverse transformation and will contain no magnetic field. The material should also be placed with it long axis in an east-west orientation to avoid any influence of the earth's magnetic field.