In the automotive industry, most of the components are consistently subjected to dynamic loadings due to random excitations from road inputs. Such loadings cause many consequences. Different loading conditions can cause different affects on component. One of this loading condition is fatigue performance of outer tie rod housing. In development phase, some tests are being done according to different types of roads to ensure that the parts are safe over complete lifetime. Forging suppliers apply cold calibration process after hot forging application, in order to ensure some critical dimensions are in the tolerance range. This cold calibration process causes residual stress on radial housing shaft. As a result, life time of housing is affected due to these residual stress at low cycles which doesn’t fulfill customer requirement. In this study, to fulfill customer requirement of ±4.95 kN at 200.000 cycle weibull(B10) evaluation, cold calibrated area is optimized. First of all, FEA analysis has been done to define most critical stress area along the shaft. It has been observed that the most critical area is close to head area. Then cold calibration process is optimized to increase the fatigue performance accordingly. New test results show that customer requirement could have been fulfilled.
Anahtar Kelimeler: Hot forging, Cold calibration, Tie rod, Fatigue
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