Q: I have a customer asking me for 17-4PH stainless, but says they need it heat treated to H1100. What does this mean?
A: 17-4PH bolts are available in many different heat treatment options. This means that different heat treatments such as H1150, H1100, H1075, etc are applied to the material after the bolt is produced in order to provide different levels of strength. Your customer is asking for H1100 which provides 150ksi ultimate tensile strength and 135 yield strength and 17% elongation. Each heat treatment available for 17-4PH bolts provides different levels of strength. Here is a chart that describes them all.
