Land Rover Defender Blog

Just What Exactly Are Land Rover Bodies Made From?

Find out about Birmabright BB2, including where it was made, how to weld it and it's physical properties

Ben Gribbin

Ben Gribbin

October 25, 2017

Hello, I'm the editor of FunRover. I'm a massive Land Rover fan. Currently own a TD5 90. 2015 MR Blogger of the Year


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A while back, we published an article about the specific alloy used to make early Land Rover bodies, Birmabright. 

One reader got in touch and shed a some light on the specific alloys involved in making Birmabright.

So what is Birmabright? Specifically BB2, as used on early Land Rovers? BB2 Birmabright is simply a trade name for the alloy AA5251 (in UK, HS4).

Chemical Composition of Birmabright (AA5251)

Element % Present
Copper 0.15
Magnesium 1.7-2.4
Silicone 0.4
Iron 0.5
Manganese 0.1-0.5
Zinc 0.15
Titanium 0.15
Chromium 0.15
Aluminium Balance

This alloy was made by a number of aluminium smelters. Birmabright was the name used by Birmetals Ltd (suppliers of BB2), who were bought out by British Aluminium and their parent company likely continue to own the trademark & rights to this day. British Aluminium continued to supply Land Rover from their falkirk plant until 2004. During the late 1970's, Birmetals brochures also referred to Birmabright by it's american standard name - AA5251.

Birmabright Properties


An alloyed non-heat treatable rolled aluminium sheet designed for general sheet metal work where higher mechanical properties are required together with a degree of formability.

Spec: BS EN 485-2:2008

Physical Property Value
Density 2.69 g/cm³
Melting Point 625 °C
Thermal Expansion 25 x10^-6 /K
Modulus of Elasticity 70 GPa
Thermal Conductivity 134 W/m.K
Electrical Resistivity 0.044 x10^-6 Ω .m

Sheet and Plate - 0.2mm to 25mm


Mechanical Property Value
Proof Stress 120 Min MPa
Tensile Strength 190 - 230 MPa
Hardness Brinell 56 HB

Welding Birmabright Land Rover Panels

All welding processes can be used on Land Rover body panels, including MIG and Tig. Recommended filler wire is 5356.

Location of Birmabright Works

Clapgate Lane, Quinton, Birmingham, circa 1945, credit Google. Note the camouflaged factory roof.

And the site today:

Other Brand names for AA5251

  • Hiduminium 22
  • Alcan GB M57s
  • BA 21
  • Alcoa 510
  • AWCO 21

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