NES835 is the naval designation for Hiduron® 191 (UNS C72420), a high-strength copper-nickel alloy developed by Langley Alloys. NES stands for Naval Engineering Standard, originally issued by the UK Ministry of Defence. It has since been replaced by Def Stan 02-835 (Def Stan is short for Defence Standard), which covers the "Requirements for High Strength Copper Nickel Manganese Alloy Forgings, Forging Stock Rods and Sections". Hiduron® 191 is therefore also referred to as Def Stan 02-835.

The Hiduron® family was developed by Langley Alloys in the late 1930s and was adopted for naval use during the Second World War. It remains in use across a wide range of industries and applications today.

Copper nickel small diameter bars available from stock
Copper nickel small diameter bars available from stock.

Hiduron® 130 and Hiduron® 191

Hiduron® 130 (DIN 2.1504, DTD900/4805) is the most widely used grade, on account of its very high strength. Hiduron® 191 (NES835) was developed later to improve impact strength, trading a small amount of the original grade's yield strength for greater toughness.

Both alloys achieve consistently high strength across a wide range of sizes through a precipitation-strengthening mechanism that develops as the bars cool after forging.

Applications

Copper-nickel alloys, also known as cupronickels, improve on the strength of copper while retaining favourable physical properties such as resistance to corrosion and fouling. This makes them well suited to naval, marine and subsea equipment. Hiduron® grades are also used in valve applications for their excellent resistance to galling, and in oil and gas components such as stab plates, connectors and couplings.

We carry stock of Hiduron® 130 and Hiduron® 191 as round bar. Hiduron® 130 is the most popular and can usually be satisfied from stock, while Hiduron® 191 (NES835) is more typically used for projects supplied from production, often as bespoke forged blocks.