Test and Reseach about Bending Fatigue Strength of Three Kinds of Baintic Ductile Iron Gears

This article sums up the testing results of bending fatigue strength of three kinds of Baintic ductile iron gears. The testing method is an accelerated test for determining the fatigue strength of gears. For calculating the bending fatigue stress 《ISO/TC60 424E Calculation of tooth strength of spur and helical gears》 is adopted.
When the number of basic cycles is No = 3×10⁶, the bending fatigue limit stresses σ_Flim（R = 0. 99） are shown as follows:The measurements and surfaces where failure occurred are analyzed.