Q: I’m looking for a high density material that is also high strength. I need set screws for a weighted part, but they also need to have about 120ksi of tensile strength. Is this possible?
A: Yes, for this type of application you’ll want to use pure tungsten or a tungsten alloy screws. Un-alloyed tungsten (99.5% pure) is not only extremely dense: 19.3 g/cc, but also strong. Tungsten alloys are slightly less dense ranging from 17 – 18.5 g/cc but can be much more economical as they have significant machining advantages. Pure tungsten screws will give you about 142ksi ultimate tensile strength (109ksi yield) and the tungsten alloys range from 94 – 110 ksi ultimate tensile (~75ksi yield).