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Aerospace buyers and engineers in the Chicago area work with tight specs and tighter schedules. When a bar arrives out of tolerance or corrodes in service, it’s not just a material problem. It becomes a program problem. That’s why 17-4 PH stainless steel round bar keeps appearing on approved materials lists across Midwest aerospace shops.
We stock it here at Forte Precision Metals in Franklin Park, IL. Engineers and procurement managers call us specifically when they need strength and corrosion resistance in one grade, and 17-4 PH delivers exactly that.
What Makes 17-4 PH the Right Choice for Aerospace Work
17-4 PH sits in a different category from standard stainless grades. It’s a precipitation hardening grade, which means it achieves high strength through a controlled aging process. Common austenitic grades like 304 and 316 simply can’t match that. You get both strength and corrosion resistance without choosing between them.
For Chicago area aerospace shops, that combination reduces the number of material substitutions mid-program. The grade performs consistently, and its machines predictably when the incoming bar stock is properly ground and straightened before it reaches your floor.
It’s Magnetic, and That Changes the Design Conversation
Unlike 303, 304, and 316, which are all non-magnetic austenitic grades, 17-4 PH is magnetic. That detail directly affects sensor housings, electronic assemblies, and structural components where magnetic response is a design variable.
Forte Precision Metals also stocks 15-5 PH, which shares a similar precipitation hardening structure. The choice between the two often comes down to geometry and downstream machining requirements. Knowing this before you finalize your spec prevents a costly substitution later in the program.
Precision Ground Stock Saves Time on Your Shop Floor
Our centerless grinding operation in Franklin Park holds tolerances as tight as plus or minus .0001 inch with a microfinish down to 8RA. We grind bars up to 7 inches in diameter and up to 24 feet in length.
A 17-4 PH bar ground to that level arrives dimensionally consistent and surface-ready. Your machinists start cutting to spec immediately instead of correcting incoming stock, which keeps your production schedule on track.
One Supplier for the Full Range of Stainless Grades
Our stainless inventory covers 302, 303, 304, 304/304L, 316, 316/316L, 316LVM, 321, 347, 410, 416, 420, 420F, 430, 430F, 440, 440C, 446, 455, 15-5 PH, X15TN, Duplex, and Bearing Shaft Quality bar. When your program uses multiple grades, sourcing from one certified supplier simplifies your qualification process.
Grade 321 carries high stress and creep rupture properties suited for pressure applications. Grade 316LVM suits high-purity and medical environments. Having all of these available from one ISO 9001:2015 certified source, certified since 1994, makes supplier management significantly cleaner.
In-House Services That Support Aerospace Tolerances
We run bar chamfering, bar straightening with rotary machines for ferrous bars, metal turning at plus or minus .001 inch, milling at plus or minus .001 inch, custom machining at plus or minus .005 inch with CNC and CAD/CAM equipped operations, precision metal cutting, and polishing up to a number 8 mirror finish.
Everything runs under one roof at 9234 Parklane Ave, Franklin Park, IL. Your 17-4 PH bar gets ground, straightened, chamfered, and cut to length before it ships. You receive stock that is ready to run the moment it arrives at your facility.
Quality Documentation Your Program Can Reference
We’ve held ISO 9001:2015 certification since 1994. Our quality system includes Advanced Quality Planning, Statistical Process Control, Gauge R&R, and Machine Capability Studies. These aren’t just credentials on paper.
When your aerospace program requires supplier quality documentation, we have the infrastructure to support that conversation. Our systems have been tested and refined over more than 30 years of serving aerospace, automotive, medical, and military customers nationally and worldwide.
Request a Quote for 17-4 PH Stainless Round Bar
Bring us the specifics of your requirement. Diameter, length, tolerance, finish, and any processing you need. We respond with something useful, not a generic price sheet.
Call us at +1 (847) 451-8888, Monday through Saturday, 7 AM to 5 PM. You can also submit your requirements at fortemetals.com/request-a-quote. We ship nationally and worldwide from Franklin Park, IL.
FAQs
Is 17-4 PH stainless steel magnetic?
Yes, 17-4 PH is magnetic. Standard austenitic grades like 303, 304, and 316 are non-magnetic. Confirm this at the design stage if magnetic response affects your assembly.
What other stainless grades do you stock for aerospace?
Forte Precision Metals carries 15-5 PH, 321, 347, 316LVM, 455, X15TN, and Duplex bar, all available from our ISO 9001:2015 certified facility in Franklin Park, IL.
What tolerances can you hold on a 17-4 PH bar?
Centerless grinding holds plus or minus .0001 inch with 8RA microfinish on bars up to 7 inches in diameter and 24 feet in length. Metal turning runs to plus or minus .001 inch. Custom machining runs to plus or minus .005 inch.
Do you ship outside the Chicago area?
Yes. We provide national and worldwide shipping from our facility in Franklin Park, IL. We can accommodate orders from any location.
