Hey there, if you’ve ever been shopping around for industrial piping, you’ve probably stumbled on Inconel steel pipes and wondered what makes them so popular—especially when it comes to handling super harsh conditions, right? I’ve been in the Inconel pipe game for over a decade now, and one question that comes up all the time from engineers, project managers, and even new folks just getting into industrial specs is: “What’s the deal with their magnetic properties?” Inconel Steel Pipe
Let’s cut through the confusion here. A lot of people assume all metal pipes are either straight-up magnetic or totally non-magnetic, but Inconel? It’s not that simple. And as someone who’s sold thousands of these pipes for applications from oil refineries to aerospace test rigs, I can tell you getting this right is not just a technical detail—it can save you a ton of headaches down the line.
First off, let’s back up with quick science (I’ll keep it plain, I promise). Inconel’s a family of nickel-chromium superalloys, right? The base is mostly nickel—usually around 70% or so, with chromium (10-20%) for corrosion resistance, plus bits of iron, molybdenum, or other elements to tweak strength. Metals that are magnetic (think plain steel pipes, iron nails) have unpaired electrons that line up in tiny regions called magnetic domains. When those domains point the same way, the metal sticks to a magnet. Non-magnetic metals like copper or aluminum have their electrons paired up, so no domains to line up.
So where does Inconel fall? Most of the time, commercially available Inconel pipes—like the super common 600 or 625 grades—are weakly magnetic, not strongly like carbon steel. But wait, that’s not a hard rule. It changes based on how the pipe was made. Let me explain: when Inconel is first cast from the furnace, it’s usually pretty non-magnetic. But as soon as we start working it—hot rolling it into pipe shapes, cold drawing to get that tight dimensional tolerance you need for industrial use—we introduce what metallurgists call “plastic deformation.” That deforms the crystal structure of the metal, creating defects that mess with those electron pairings, and boom—now you’ve got some weak magnetism.
I see this all the time with new clients. A guy from a food processing plant (needs non-magnetic piping for safety standards) once called me panicking because he tested a sample with a magnet and it stuck a little, so he thought it was wrong. I sent a tech over to test their 304 stainless pipe too (you know, the standard stuff they use), and that stuck even stronger. The Inconel was only pulling the magnet slightly. That’s totally normal.
Now, why does this matter for your project? Let’s break down the real-world use cases. If you’re working on a place where magnetic interference is a no-go—like MRI rooms, or electrical substations, or even some semiconductor manufacturing lines—you need to know how much magnetism you’re dealing with. Weak magnetic is usually fine, but if you absolutely need zero magnetism, you can ask for Inconel that’s been “annealed” after forming. Annealing is basically heating the pipe up to a super high temperature (like 2000°F for Inconel 625) and slowly cooling it down. That lets the crystal structure settle, fixes those deformation defects, and brings the magnetism way down—almost back to what it was in the cast state.
Wait, but here’s another twist: not all Inconel grades are the same. Inconel 718, which is super popular for aerospace and turbo parts, is actually a little more magnetic than 600 or 625. That’s because of the extra niobium and aluminum in its composition, which changes how the crystals behave when deformed. I always tell clients to tell me their specific grade requirement upfront because if you’re buying 718 and expecting it to be non-magnetic, you’ll be disappointed unless you get that post-forming anneal.
Let me also bust a myth I hear all the time: “If it’s weakly magnetic, it’s not real Inconel.” Nah, that’s garbage. Carbon steel is strongly magnetic, stainless steel is usually weakly magnetic (some grades are more than others), and Inconel’s weak magnetism is just part of its makeup. I’ve tested hundreds of samples over the years—we have a little fridge magnet on every sales rep’s desk for quick checks—and the real stuff only pulls it a little. If a sample’s sticking like crazy, that’s probably not Inconel at all, or it’s been mixed with too much iron (a bad batch, or maybe a knockoff).
Now, let’s talk about how this magnetic property interacts with Inconel’s main superpowers, because that’s why you care about it in the first place. Inconel’s famous for withstanding extreme heat, corrosive chemicals, and pressure that would make carbon steel crumble. The magnetism doesn’t change any of that—at least, not in the range you’d use it. I’ve seen Inconel pipes go through 1800°F furnaces, sit in saltwater for years, and their magnetism barely shifts. The only time I’ve seen it change is if the pipe gets super cold, like cryogenic temps for liquid natural gas. Even then, it’s just a tiny bump in magnetism, nothing that would affect anything.
So what should you do when you’re ordering Inconel steel pipe? First, be honest with your supplier (that’s me, by the way) about your magnetic requirements. Tell them if you need something that’s as non-magnetic as possible, or if weak magnetism is totally fine. We test every batch we ship, and we can provide a material test report (MTR) that specifically notes magnetic permeability, which is the actual measure of how magnetic the pipe is. MTRs are non-negotiable for most industrial projects anyway, so adding that to it is no big deal.
A quick example: last year, I worked with a team building a new nuclear power plant. They needed Inconel piping for the reactor coolant system, and magnetic interference could mess with their monitoring sensors. We sent them Inconel 600 pipes that had been fully annealed, tested the permeability to make sure it was below their 0.05 µr threshold, and they didn’t have a single issue on-site. That’s the kind of detail that makes us different from random online suppliers—we don’t just sell you a pipe, we make sure it fits your exact needs.
Another example: a petrochemical client was replacing their old carbon steel piping with Inconel to handle sour gas (super corrosive stuff). They didn’t care about magnetism at all—they just needed the corrosion resistance. The weakly magnetic Inconel was perfect, and they saved 30% on their order by skipping the extra anneal step. That’s why it’s important to communicate both your specs and what you don’t need.
If you’re still on the fence about magnetic properties, here’s a cheat sheet I give all new clients:
- As-cast, annealed Inconel: Very weakly magnetic (hardly noticeable, magnet barely sticks)
- Formed (hot rolled, cold drawn) Inconel: Weakly magnetic (magnet sticks a little, way less than steel)
- Inconel grades: 600 and 625 are less magnetic than 718 or 750
- For zero to negligible magnetism: Ask for post-forming full anneal, and request permeability data in your MTR
At the end of the day, the magnetic properties of Inconel pipes are a small but important part of the overall package. They don’t make or break whether the pipe works in extreme heat or resists corrosion, but getting them right can save you from costly delays, failed inspections, or even project shutdowns.
If you’re getting ready to order Inconel steel pipe, whether it’s a small batch for a repair or a huge run for a new project, hit me up to chat through your needs. We’ll walk through all the specs, including magnetic requirements, make sure you get exactly what you need, no guesswork, no junk.
Happy to help—just reach out anytime.
Alloy Steel Pipe References:
- Davis, J.R., ed. (1994). Nickel, Cobalt, and Their Alloys. ASM International.
- Brandes, E.A., Brook, G.B., eds. (1998). Smithells Metals Reference Book, 7th ed. Butterworth-Heinemann.
- American Society for Testing and Materials (ASTM). (2020). Standard Specification for Nickel-Chromium-Iron Alloys (UNS N06600, N06601, N06603, N06690, N06693, N06025, N06045, N06098, and N06099) for Seamless Pipe and Tube. ASTM B163.
Zhengzhou Huitong Pipeline Equipment Co., Ltd.
Zhengzhou Huitong Pipeline Equipment Co., Ltd. is one of the leading inconel steel pipe manufacturers and suppliers in China. Find the best quality and durable inconel steel pipe with competitive price here from HT PIPE. Welcome to place orders, and the customized orders are also accepted in our factory.
Address: 7 Floor,4th Building,Jinyin Modern City,Jinshui District,Zhengzhou City,China,450000
E-mail: specialmetal@htpipe.com
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