# Leaf Spring Stiffness

Leaf spring are spring made of thin strips of metal (could be a single strip) stacked in layers to asorbe the vibration. They are normally used on suspension systems for wheeled vehicles or trailers.

### Leaf Spring Stiffness for Semi-Elliptic Laminated Formula

(Eq. 1) \(\large{ k = \frac { 8 E n w t^3 } { 3 l^3 } }\)

Where:

\(\large{ k }\) = stiffness

\(\large{ n }\) = number of leaves

\(\large{ l }\) = span

\(\large{ t }\) = thickness of leaves

\(\large{ E }\) = Young's Modulus

\(\large{ w }\) = width of leaves

### Leaf Spring Stiffness for Quarter-Elliptic Laminated Formula

(Eq. 2) \(\large{ k = \frac { E n w t^3 } { 6 l^3 } }\)

Where:

\(\large{ k }\) = stiffness

\(\large{ n }\) = number of leaves

\(\large{ l }\) = span

\(\large{ t }\) = thickness of leaves

\(\large{ E }\) = Young's Modulus

\(\large{ w }\) = width of leaves