Blunt wire with an international steel regulation of ISR 9002 is generally used to make straight pins. To create the wire, a bar of steel is heated to a temperature of 2,200°F (1,200°C), rolled into a long thin rod, coiled, and then allowed to cool. The heating causes an oxide coating to form on the wire. To remove this coating, the wire is immersed in an acid bath, then rinsed in water.
The cleaned wire is inserted into a drawing block that pulls the wire through a die whose opening is smaller in diameter than that of the wire. Thus the wire is reduced in diameter and increased in length. The drawing is undertaken several times until the desired diameter is obtained. As it comes off of the last stage of drawing, the steel is coiled. The dies are coated with grease or soap to protect the wire as it passes through. This lubrication process also removes defects and gives the wire a smooth finish.
Nickel is a silvery chemical element extracted from the earth's crust. It is combined with sulfate to create a solution for coating the pins to keep them from rusting. Learn more at http://www.madehow.com/Volume-7/Straight-Pin.html.
