On Material Substitution and Quick Fatigue Life Estimates Thereof in Chassis Frames

Commercial vehicle industry is often provoked to assess suitability of the most currently available steels in lieu of traditionally used ones. Such material substitutions are attempted even if the existing ones happen to be tried, tested and proven over a period of time. Motivation for an exercise of this sort is usually from the considerations of favorable cost, availability, manufacturability, durability, strength-to-weight ratio, etc. A rigorous route to carry-out such a feasibility study would be through physical prototyping and testing. This is usually an expensive and time consuming proposition. Virtual analysis, on the other hand is a more viable option. This paper proposes an even easier alternative of using the available test data to estimate fatigue life of an identical component made of a different material through use of established rules such as Neuber's. The results obtained are quite satisfactory and offer an acceptable methodology to assess improvement in fatigue life due to alternate steels without taking recourse to either ground-up physical testing or numerical analyses.