Mechanical Performance Analysis Of Aluminum Alloy Steering Knuckle Based On Adams Load Decomposition

Lightweight is an effective way to reduce harmful emissions and energy consumption.As one of the most important components of automobile suspension,steering knuckle not only bears the quality of spring,but also bears the harsh and complex working conditions in the course of driving.It requires high structural strength.Therefore,steering knuckle is mostly made of cast iron with high strength,but its shortcoming is that its quality is large,and its structure is already quite compact,so it is difficult to further lighten the structure.At present,more and more automobile manufacturers are choosing to change the cast iron steering knuckle to the aluminum alloy steering knuckle.However,directly changing to the aluminum alloy material will easily lead to structural stiffness and strength shortage,which will lead to vehicle safety problems.Therefore,it is necessary to carry out a new structural development and design for the lightweight steering knuckle.Based on the lightweight research of steering knuckle of a best-selling B-class car,the mechanical properties of the aluminum alloy steering knuckle structure designed by topology are studied in this paper.The steering knuckle is decomposed by multi-body dynamics.The strength,stiffness and fatigue properties of the steering knuckle are analyzed by finite element analysis and fatigue simulation.The steering knuckle bench is used to carry out the parts.The durability fatigue life test was analyzed and verified,and the aluminum alloy steering knuckle with good service performance was obtained.Firstly,the vibration test data of the whole vehicle bench are collected to provide basic data for the verification of multi-body dynamic model.The multi-body dynamic model of the target vehicle is established by using ADAMS software,and the multi-body dynamic model is debugged by simulating and analyzing the excitation of the suspension,such as the two-wheel co-directional and lateral force test,as well as the correction moment test.Then the multi-body dynamic model of the vehicle is validated by using the response signal of the vibration test of the whole vehicle bench and the virtual iteration technology.Then,aiming at the development goal of lightweight steering knuckle,eight typical extreme conditions are selected to extract the hard point load.The static strength,stiffness,modal and fatigue strength of the aluminum alloy steering knuckle are analyzed by using finite element analysis software.Finally,through the endurance test of steering knuckle under five fatigue conditions: longitudinal endurance,vertical endurance,pull rod endurance,braking endurance and steering endurance,it is verified that the lightweight aluminum alloy steering knuckle meets the actual performance index of the product,and provides a feasible technical route for lightweight design of other parts in chassis suspension.