304 Stainless Steel Blank Round Discs — Precision-Cut Metal Circles for Fabrication, Craft & Industrial Use
When your project demands a flat, corrosion-resistant metal blank that holds tight tolerances and machines cleanly, finding the right disc in the right size can be frustrating. These 304-grade stainless steel blank round discs are stocked in an extensive range of outer diameters (6–80mm / ~0.24–3.15 in) and wall thicknesses (1–5mm / ~0.04–0.20 in), so metalworkers, fabricators, and serious DIYers can order exactly what they need without cutting down oversized sheet stock.
Each disc is a flat, circular blank cut from 304-grade austenitic stainless steel sheet. The inner diameter (ID) and outer diameter (OD) dimensions are expressed in the variant selector as ID × OD — for example, "6mm × 1mm" means a 6mm inner diameter with a 1mm wall, giving a total OD of 8mm. Discs are supplied in pack quantities ranging from 1 to 50 pieces depending on size, making them suitable for both prototyping and small-batch production runs.
Typical applications include custom gaskets and shims for plumbing and HVAC systems, decorative inlays and jewellery blanks, laser-engraving and etching substrates, weld-on backing rings for pipe joints, and structural spacers in machinery and automotive builds. The 304 alloy's balanced chromium-nickel composition makes these stainless steel round discs a reliable choice wherever mild-acid or moisture exposure is a concern.
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Compatibility note: Variant dimensions are listed as ID × Wall Thickness. Total OD = ID + (2 × Wall). Confirm your required OD before ordering. Not recommended for strong chloride or marine-immersion environments without additional surface treatment.
✅ Key Features of These 304 Stainless Steel Round Discs
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304 Austenitic Alloy
Contains 18% chromium and 8% nickel for solid oxidation resistance in indoor, outdoor, and mildly corrosive environments — without the brittleness of lower-grade steels.
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Wide Size Matrix
OD range from 8mm to 90mm (approximately 0.31–3.54 in) across the full variant grid; wall thicknesses from 1mm to 5mm (0.04–0.20 in) let you dial in the exact cross-section your design requires.
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Machinable & Weldable
304 SS machines with standard HSS or carbide tooling and TIG/MIG welds cleanly. Suitable for drilling, tapping, grinding, and polishing without special pre-treatment.
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Flat, Burr-Minimised Blanks
Discs are supplied with flat faces and edges that are suitable for direct use as gaskets, shims, or decorative elements — light deburring may be needed for precision-fit applications.
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Flexible Pack Quantities
Available in packs of 1, 2, 5, 10, 20, or 50 pieces depending on disc size, so you can order a single prototype or a small production batch without committing to bulk minimums.
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Broad Application Range
Used as gaskets, shims, weld backing rings, decorative blanks, engraving substrates, and structural spacers across plumbing, HVAC, automotive, jewellery, and general fabrication trades.
📐 Technical Specifications — 304 Stainless Steel Round Disc
| Material |
304 Grade Austenitic Stainless Steel |
| Form |
Flat blank round disc (no centre hole) |
| Inner Diameter (ID) Range |
6mm – 80mm (approx. 0.24 – 3.15 in) |
| Wall Thickness Range |
1mm – 5mm (approx. 0.04 – 0.20 in) |
| Total OD |
See variant options (ID + 2 × Wall) |
| Surface Finish |
See variant options |
| Tensile Strength (typical) |
Typically 515–620 MPa (304 standard range) |
| Hardness (typical) |
Typically ≤ 201 HB (annealed condition) |
| Pack Quantity |
See variant options (1 / 2 / 5 / 10 / 20 / 50 pcs) |
| Magnetism |
Slightly magnetic after cold working; non-magnetic in annealed state |
| Weldability |
TIG / MIG weldable; filler ER308L recommended |
| Machinability |
Machinable with HSS or carbide tooling |
❓ Frequently Asked Questions
How do I read the size options — what does "ID × Wall" mean?
The variant label shows Inner Diameter × Wall Thickness. The total outer diameter equals ID + (2 × Wall). For example, a "20mm × 2mm" disc has an inner diameter of 20mm and a wall of 2mm on each side, giving a total OD of 24mm. Always calculate your required OD before selecting a variant.
Are these discs solid or do they have a centre hole?
These are solid flat blanks — there is no pre-drilled centre hole. The "ID" in the size label refers to the inner diameter of the annular ring (the disc's bore), not a through-hole. If you need a specific bore, you can drill or punch one to your required diameter after receiving the disc.
Will 304 stainless steel rust or corrode in outdoor use?
304 SS offers solid resistance to atmospheric oxidation, fresh water, and mild acids. It is not recommended for prolonged immersion in chloride-rich environments (e.g., seawater or de-icing salt exposure) without additional surface treatment. For those conditions, 316-grade stainless steel is a better choice.
Can I weld or machine these discs?
Yes. 304 stainless steel is TIG and MIG weldable — use ER308L filler wire for best results. It machines with standard HSS or carbide tooling; use cutting fluid and moderate speeds to avoid work-hardening the surface. Drilling, tapping, grinding, and polishing are all achievable with standard workshop equipment.
How do I choose the right wall thickness for my application?
Thinner walls (1–1.5mm) suit lightweight gaskets, decorative inlays, and engraving blanks where rigidity is less critical. Mid-range walls (2–3mm) work well for structural shims, weld backing rings, and general fabrication. Thicker walls (4–5mm) are appropriate for load-bearing spacers, heavy-duty gaskets, and applications requiring significant compressive strength.
Are the discs compatible with food-contact or medical applications?
304 stainless steel is widely used in food-processing equipment and is generally considered food-safe when properly finished. However, these blanks are supplied as raw machined stock and have not been certified or tested for specific food-contact or medical-device standards. If your application requires compliance with FDA, NSF, or ISO 13485 standards, please contact us to confirm suitability before ordering.
What pack size should I order for a prototype vs. a production run?
For prototyping or testing fit, the 1- or 2-piece packs let you validate dimensions without committing to larger quantities. For small production runs or workshop stock, the 10-, 20-, or 50-piece packs offer a lower per-unit cost. Pack availability varies by disc size — check the Qty(pcs) dropdown after selecting your ID × Wall variant.
🛒 Select your Size (ID × OD) and Qty above, then add to cart.
