How can the shear strength of a steel rod be improved? The application I am thinking of is rods used to make bolts where we want the bolt to resist being sheared off after it is attached.
Some of the possibilities I see are forging the rod in some way rather than rolling it. Rolling the threads, as opposed to cutting them, and by heat treatment and tempering. How can I quantify such treatments on shear strength? Are there are other methods not mentioned?