I need to know on which base a projecter of a connecting rod can choose steel or alluminium for material in which is made.
Taking account the fact that the major stress are those due to inertia loads, the 2 materials have same performances:
σ / ρ = between 100 and 200 for both alluminium and steel alloys (berillum 300)
So connecting rods in alluminuim and steel have the same shape and volume for the same performance under inertia loads.
![Rolling Eyes :roll:](./images/smilies/icon_rolleyes.gif)
Secondary effects are those related to axial stresses due to gas pressure (here steel takes an advantage because of his major yield stress) and those due to vibration trasmission on the ground and bearings (alluminum takes an advantage due to his lower ρ)
thanks to who will help me