Neutral Axis In Sheet Metal

The k factor in sheet metal working is the ratio of the neutral axis to the material thickness.

Neutral axis in sheet metal.

K factor in sheet metal bending is a constant used to calculate sheet metal flat length or flat pattern. The line where the transition from compression to stretching occurs is called the neutral axis. The k factor in sheet metal working is the ratio of the neutral axis to the material thickness. When metal is bent the top section is going to undergo compression and the bottom section will be stretched.

The granular bonds are stretched pulled and sometimes break forcing the grains apart as they come under tensional stresses. The bend allowance describes the length of the neutral axis between the bend lines or in other words the arc length of the bend. When metal is bent the top section is going to undergo compression and the bottom section will be stretched. Where t is the distance.

K factor k can be defined as follows. K factor is a ratio that represents the location of the neutral axis with respect to the thickness of the sheet metal part and depends on material thickness and bend radius. So if the thickness of the sheet was a distance of t 1 mm and the location of the neutral axis was a distance of t 0 5 mm measured from the inside bend then you would have a k factor of t t 0 5 1 0 5. Mathematically k factor value is equal to the ratio of position of neutral axis and sheet thickness.

The line where the transition from compression to stretching occurs is called the neutral axis. When the sheet is flat without any applied stress the neutral axis is in the middle of the sheet. The bend allowance and bend deduction are two measures that relate the bent length of a piece of sheet metal to the flat length. But add a little stress and force the metal to bend and watch what happens.

When a piece of metal is being formed the inner portion of the bend compresses while the outer portion expands see figure 1.