When metal is bent the top section is going to undergo compression and the bottom section will be stretched.
Neutral axis in sheet metal.
The location of the neutral axis for a specific sheet is defined by a factor called k factor.
K factor in sheet metal bending is a constant used to calculate sheet metal flat length or flat pattern.
When a piece of metal is being formed the inner portion of the bend compresses while the outer portion expands see figure 1.
When the sheet is flat without any applied stress the neutral axis is in the middle of the sheet.
Mathematically k factor value is equal to the ratio of position of neutral axis and sheet thickness.
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.
But add a little stress and force the metal to bend and watch what happens.
In sheet metal the k factor is the ratio of the neutral axis to the material thickness.
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.
K factor a constant determined by dividing the thickness of the sheet by the location of the neutral axis which is the part of sheet metal that does not change length.
The line where the transition from compression to stretching occurs is called the neutral axis.
The bend allowance describes the length of the neutral axis between the bend lines or in other words the arc length of the bend.
The line where the transition from compression to stretching occurs is called the neutral axis.
When metal is bent the top section is going to undergo compression and the bottom section will be stretched.
K factor k can be defined as follows.
The bend allowance and bend deduction are two measures that relate the bent length of a piece of sheet metal to the flat length.
The granular bonds are stretched pulled and sometimes break forcing the grains apart as they come under tensional stresses.