17-7 Stainless Steel Tubing: A Great Alternative

By Katie Karmelek
September 24, 2020

I’ve been working on some innovative devices and delivery systems lately. As these devices become more complex with longer lengths and thinner walls, we often design in a 300-series stainless steel tube for strength without giving up too much real estate in the device. 

Recently, I came across 17-7 SS as an alternate solution, and was surprised by some of the material properties that allowed us to optimize the product design. Compared to 304 SS, 17-7 has a higher tensile strength, improved machinability, weldability and magnetic permeability. 

I often find real-life examples helpful when I’m learning about new technologies that give me a framework and understanding of how it may apply to the products I’m developing. Here’s one from Accu-Tube’s recent whitepaper on Metal Tubing Specs:

A customer came to Accu-Tube looking for help designing a next-generation orthopedic driver. Early testing of the device using 304 tubing resulted in mechanical failure with a fixed ID and OD due to the interaction of the tube with the balance of the device. The customer needed a stronger tube, and 304 or 316 alloys would not meet that goal. Accu-Tube’s team suggested exploring 17-7 as an alternative. With a higher tensile strength than 304 and the ability to heat treat to further increase its strength, 17-7 looked very attractive on paper. 

The Accu-Tube team worked for 3 months to develop the entire manufacturing process, and the result was a tube that exceeded the performance requirements of the design.

Interested in learning more about 17-7? Check out Accu-Tube’s website. Or try 17-7 out for yourself to see if it works for your project. We have ~60 in-stock skus or you can request a custom component.