Material Focus: 17-4 Bolts for Extreme Strength

High strength bolts are one of the main reasons engineers look to specialty materials. 17-4PH bolts often fulfill this demand. In this short newsletter we hope to answer many of your questions surrounding the age-hardened stainless steel we call 17-4PH
How much strength can 17-4PH provide?
17-4PH bolts can provide up to 4 times the strength of stainless 316 fasteners depending on the heat treatment.
Heat treatment: What is it and how do I choose?
Heat treating of the 17-4PH alloy involves a heating and cooling process that enhances its mechanical properties. Different heat treatments (aging processes) provide different levels of strength and hardness.This chart provides a list of the heat treatments (also known as the aged conditions). Beside each heat treatment it also displays the specific strength and hardness they provide. For example, H900 will provide a stronger and harder material than H1150 but also be the most brittle with the least elongation.
What is annealed 17-4PH?
Annealed means that the 17-4PH bolts were not heat treated. This is called 17-4PH Condition A.
Is 17-4PH also useful for high temperature applications?
17-4PH bolts have a maximum usable temperature of about 600°F. In the anneal condition, this maxes out a little lower and should not be used above 572°F.
Can 17-4PH be used for corrosive environments?
17-4PH bolts are typically not used for corrosion like a nickel alloys, however its resistance to common corrosive environments is better than 400 series steel; being most similar to 304 stainless. The heat treating process can also make 17-4PH more susceptible to stress corrosion cracking, which can be a concern in applications where chloride stress corrosion cracking is possible.
So while its not really a very corrosion resistant alloy, it is a stainless steel and will typically corrode in ambient conditions. When high strength and corrosion resistance are needed, there may be more suitable options.
This entry was posted in Application, Blog, High Strength, Material, Specialty Metal Fasteners and tagged , , , , , , , , , , . Bookmark the permalink.

Leave a Reply

Your email address will not be published. Required fields are marked *

Fragen?

Unsere Materialexperten stehen bereit, Sie bei Ihrer spezifischen Anwendung zu unterstützen.

Kontaktieren Sie einen Experten