Description
The Machinist’s Choice for Precision Components
We’ve spent years working with manufacturers who need stainless steel that actually performs on the shop floor. That’s where our 303 Free-Machining Stainless Steel Round Bar stands out. It’s not just another grade – it’s the go-to material for shops where tool life and cycle times matter as much as corrosion resistance. The added sulfur (0.15-0.35%) makes a real difference in chip breaking, especially when you’re running high-speed CNCs all day.
You’ll notice the difference immediately: up to 60% faster machining compared to standard 304, with 100% rating relative to 12L14 carbon steel. We’ve seen customers reduce tool changes by nearly half on complex shaft work. The trade-off? Slightly less weldability – but when you need machinability, this is where it’s at.
Where Performance Meets Practical Demands
- Automotive transmission shafts: Our 303 holds ±0.0005″ tolerances on ground diameters, critical for spline fits. One Tier 1 supplier cut their finish grinding time by 35% switching from 304.
- Medical instrument housings: The polished finish (Ra ≤ 16 μin available) works well for sterile environments, though we remind customers it’s not for implant use.
- Valve stems and fittings: Performs reliably with organic acids and nitric acid washes, though we recommend 316L for saltwater exposure.
Key specs that matter in real-world use:
– Consistent hardness (≤262 HB) prevents galling during tapping
– 35% elongation means it survives cold forming operations better than most free-machining grades
– ASTM A582/A582M certified with full mill test reports – no surprises in your PPAP process
From Stock to Custom – We Speak Your Language
Based in China’s stainless steel hub, we’ve supplied everything from 5,000-piece runs of 3mm dowel pins to custom 250mm diameter bars for specialty chemical valves. Our annealing process ensures uniform machinability across full cross-sections – a detail we know matters when you’re deep drilling 10:1 L/D ratios.
Need something non-standard? We regularly provide:
* Bars with ground OD + polished finish (critical for hydraulic shafts)
* Custom lengths from 100mm to 6m with ±0.05mm length tolerances
* Pre-machined features like center holes or keyways
We’re not just a supplier. We’ve helped aerospace customers qualify this material for non-critical fittings, and we understand the documentation needed for medical device manufacturing. When a European customer needed 303 bars with EN 10204 3.1 certification, we delivered within three weeks.
If your project needs reliable machinability without the guesswork, let’s talk. We’ll ask the right questions about your tooling, tolerances, and volumes – then get you the right material, not just a grade.
