Door Hinge Materials: Stainless Steel, Brass, Zinc Alloy and Iron

Updated 2026-11-05 · RAYEN 雷茵

What should you find out before choosing?

• Where the door is: indoors and dry, in a bathroom, or near the coast.
• What the customer will see: a brass tone, a steel tone, or a coloured finish.
• Door weight, and whether the hinge shows.
• Whether you need the same look across other hardware.

Stainless steel: which grade?

Most ball bearing hinges in the range are listed as Stainless Steel (304/201). That means the same model can be made in either grade, so one line on your order decides it. 201 suits dry interiors. For damp rooms, or a buyer who asks for 304, write 304. Ask for the grade in writing, because a magnet is not a reliable test.

Concealed hinges use other grades. The R-CS, R-CC, R-CF and RY series are 304/316L. EDA-39 and EDA-40 are 304. If the site is close to the sea, tell us, and write 316L against those models.

Brass: why is there no pure copper hinge?

You will see pure copper hinges offered in the Chinese market. It is a trade name. Pure copper is too soft to carry a door, so these hinges are brass or another alloy. Every hinge in our range made from a copper alloy is brass, and we write it that way.

Two more words cause confusion. Frosted Copper, the usual finish on our brass hinges, is a colour name. And 2DD on a code such as 4x3x3.0-2DD means two copper gaskets inside the knuckle joints. The leaves are still brass.

Does the material change the hinge size?

Yes, and this is the mistake that costs a re-route. The same code can be a different part in another metal.

• 4x3x3.0-4BB in stainless is 101.6 × 76.2mm with a Ø14.2mm knuckle.
• 4x3x3.0-4BB in brass is 100 × 75mm with a Ø12mm knuckle.

Even where the leaf matches, the knuckle may not. 4x4x3.0-4BB in stainless and 4x4x3.0-4BB in brass share a 101.6 × 101.6mm leaf, at Ø14.2mm and Ø14mm.

Sorted by knuckle, you can see the pattern. Brass runs from Ø10mm to Ø14.6mm. Stainless runs from Ø12.2mm to Ø16.2mm.

Is the finish the same as the material?

No, and a colour name can mislead. In stainless, 4x3x3.0-4BB comes in Satin Sanded, Matt Antique Bronze, Matt Antique Copper, Gunmetal Grey and Matt Antique Brass. All five are stainless steel underneath. In brass, 4x3x3.0-4BB comes in Frosted Copper, Matt Antique Bronze, Galaxy Grey, French Bronze, Black Antique Brass, Brushed Chrome, Brushed Nickel and Coffee. All eight are brass underneath.

So a buyer can get a bronze look on a stainless hinge, or a chrome look on a brass one. Always write the material and the finish as two separate words on the order.

Zinc alloy: where does it appear?

Zinc alloy is the body of most of our EDA concealed hinges.

The zinc alloy models run from 40kg to 100kg on two hinges. When the door is heavier, the series moves to 304 stainless: EDA-39 carries 120kg and EDA-40 carries 200kg. The concealed hinge load chart compares them with the R-series.

Iron: where does it appear?

4x4x2.5-3D is listed as iron and zinc alloy. Its leaf is 103 × 102mm and 2.5mm thick, in Sand White, Satin Gold, Tea Brown or Matt Black. It is the one adjustable butt hinge here. Keep it for dry interiors, and tell us if the door is going anywhere damp.

What about aluminium?

Aluminium appears on our hydraulic hinges. RY8005, RY8006 and JL606 are listed in aerospace aluminium. See hydraulic hinge types.

A worked example

A hotel near the sea wants concealed hinges, a door of 50kg to 60kg, and a black finish. R-CS80 carries 80kg, and the series comes in Matt Black. Write 316L on the order, then Matt Black. Do not take a zinc alloy EDA model just because it is also offered in black, unless you have told us the site and we agree it suits.

What should you write on the order?

• Model code.
• Metal, with grade: 304, 201, 316L or brass.
• Finish, as a separate word.
• Leaf size in mm, from the row for that material.
• Where the door will be, if it is damp or coastal.

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