A study on precision cold forging process improvements for the steering yoke of automobiles by the rigid–plastic finite-element method

The steering column in a steering system, one of the main devices of an automobile, is a very important part to attain stability and steady movement of the vehicle. The steering yoke, the core part of steering column is manufactured through various processes, such as hot forging, machining, and assembly by welding. This study proposes a new method for manufacturing an united steering yoke of high manufacturing productivity, improved mechanical properties and low cost through precision cold forging. The rigid–plastic finite-element method for precision cold forging has been used in order to reduce development time and die cost. Practical considerations in the manufacturing stage such as hardness in heat treatment, and coating condition in lubrication have also been investigated. The results have been applied successfully in mass production.