# Dynamic Cornering Fatigue Test of a Rim

This rim is designed with CAD program. It has width 8 inch, ET 50 mm, 5 wheel bolt holes and distance of holes 110 mm.

I chose the AlSi7Mg alloy which is usually used for manufacturing of rim. This alloy has that properties:

Mechanical and Volumetric Properties:

Mass: 8.2046 kg

Density: 2650 kg/m3

Volume: 0.00306142 m3

Yield strength: 190 MPa

Young’s Modulus: 72 GPa

Poisson ratio: 0.32

Boundary Conditions

Bending moment calculates on a rim as:

M=(uR+d) FvS

M= F (load) x l (moment arm)

R: diameter of tire (0,30 m)

D: distance of offset (0,050m)

U: coefficient of friction

S: coefficient of fatique ( For aluminum 2, steel 1,6)

Fv: Static force on drive shaft (600 kg x 9.81 N/kg  = 5886 N)

M= (0,30 x 0,9 + 0,050) x600 x 9,81 x 2= 3767 Nm

moment arm depends on test device which is get 650mm by us. According to this, force is as:

3767 Nm= F x 0.650 m

F=5795 N

Simulation of Test

Analysis

Maksimum stress of Von Mises is 143 MPa on rim. According to result of analysis, stress on rim is lower than yield strength of aluminum alloy.

The maksimum stress  occurs to arms of rim which is 143 MPa.

Maximum stress in Wheel bolt holes is 69.621 MPa.

Maximum displacement of rim according to applied moment (3767 Nm) is 0.276 mm .

Result of Test

In this analysis,dynamic fatigue cornering test had been applied to rim simulated on Hyperworks. The simulation is occured that at direction x  and angle of 0 degree, calculated bending moment, impact of 5795 N force.  As material of rim had been used AlSi7Mg alloy.

Result of applied maximum bonding moment, maximum  Von Mises stress had been determined 143 MPa. Maximum stress is in arms of rim.  AlSi7Mg alloy has 190 MPa yield  strength. So rim is in elastic region.

We determined value of maximum stress for 600 kg load drive shaft. However, more load drive shaft, maksimum stress closes yield of strenght our material. So we can comment that it has geometrical problems.