What DIN 86019 and ASTM B466 Cover
The 90/10 copper nickel tube is governed by two families of specification that are often quoted together. ASTM B466, issued in parallel as ASME SB466, is the specification for seamless copper-nickel pipe and tube and defines UNS C70600 for general industrial and marine service. DIN 86019 is a shipbuilding specification for seamless tubes of copper-nickel alloys and designates the 90/10 composition as CuNi10Fe1.6Mn under material number 2.1972, with dimensions organised in DN-based series that match shipboard piping practice. The two documents therefore answer different questions: B466 fixes the alloy chemistry and mechanical requirements, while DIN 86019 fixes the dimensional and tolerance system for piping installed on board ship. A purchasing enquiry should state which of them governs, because the wall thickness series and the permitted iron range can differ between an ASTM order and a DIN order for what is nominally the same alloy.
Chemical Composition and Mechanical Properties
The composition window below follows the C70600 limits of ASTM B466 and ASTM B111. Iron is a deliberate and essential addition: it is what gives 90/10 copper nickel its resistance to impingement attack in flowing seawater, and the DIN 86019 grade name CuNi10Fe1.6Mn records that the iron content is held towards the middle of the range. Manganese supports hot workability, and carbon, lead and zinc are held to low residual maxima.
| Element | Limit (wt.%) |
|---|---|
| Copper | Remainder |
| Nickel | 9.0 - 11.0 |
| Iron | 1.0 - 1.8 |
| Manganese | 1.0 max |
| Zinc | 1.0 max |
| Lead | 0.05 max |
| Carbon | 0.05 max |
| Property, annealed seamless tube | Value |
|---|---|
| Tensile strength | 275 MPa (40 ksi) minimum |
| Yield strength, 0.5% extension under load | 105 MPa (15 ksi) minimum |
| Elongation | Specified by the standard according to temper and wall thickness |
| Density | Approximately 8.94 g/cm³ |
International Equivalents of 90/10 Copper Nickel
The same alloy is designated differently across standards bodies, and export enquiries frequently quote two or three designations together. The table below lists the designations most often seen on 90/10 copper nickel tube documentation.
| Standard | Designation |
|---|---|
| ASTM B466 / B111 / B171 | C70600 |
| ASME SB466 / SB111 | C70600 |
| DIN 86019 / material number 2.1972 | CuNi10Fe1.6Mn |
| DIN 17664 | CuNi10Fe1Mn |
| EN 12449 | CW352H |
| JIS H3300 / KS D5301 | C7060T |
| BS 2871 Part 2 | CN102 |
| AS 1752 and EEMUA 144 | C70600 and 7060X |
Typical Applications in Marine and Industrial Service
Marine: seawater piping systems, condenser and heat exchanger tubes, tube sheets and baffles for salt water service, boat hull fittings, propeller sleeves and hot water tanks.
Power and process: condensers, evaporators, distiller tubes, valve bodies, pump impellers and pressure vessels in refineries and desalination plants.
Industrial: weld torch tips, ferrules, condenser plates and fittings exposed to chlorides.
Automotive: power steering tube and brake lines, where resistance to road salt matters.
Because copper nickel resists marine biofouling far better than steel or aluminium bronze, pumps and piping built from it keep their design flow rates without chemical dosing or frequent cleaning.
Fabrication, Welding and Installation Guidance
Seamless 90/10 tube is readily bent, flared and rolled into tube sheets, and it is welded with matching copper-nickel filler. Fusion welding should use low heat input with a nickel-bearing filler that matches the base alloy, and the joint area must be clean and dry before welding because carbon and sulfur contamination embrittles copper nickel at temperature. Heat treatment after welding is generally unnecessary for thin-wall tube, but cold-formed sections intended for seawater service are normally stress relieved to reduce residual stress. Tube ends should be deburred and the inner surface left free of scale so that flow remains uniform; scale and weld spatter create the local turbulence that starts impingement attack. When two different copper-nickel alloys or a copper-nickel tube and a steel shell are joined, insulating gaskets and careful selection of dissimilar-metal fasteners prevent galvanic corrosion of the less noble component.
Inspection and Ordering Points
Order documentation for 90/10 tube should identify the governing specification, the UNS or DIN designation, the temper, the delivered condition, outside diameter, wall thickness and length, and the test schedule. Seamless tube for seawater duty is normally supplied with hydrostatic or pneumatic pressure testing, eddy-current examination, chemical analysis and tensile testing reported on a certificate traceable to the heat number. Dimensional inspection should confirm ovality and wall eccentricity, because an off-centre wall reduces the pressure rating and creates a thin side that corrodes first. Where DIN 86019 governs, dimensions and tolerances follow the DN series of that standard rather than an arbitrary diameter and wall combination, so the tube will fit the fittings, flanges and expansion joints already specified for the vessel.
FAQ
Q: Are DIN 86019 and ASTM B466 the same specification?
No. Both describe seamless 90/10 copper nickel tube, but DIN 86019 is a shipbuilding specification built around DN dimensional series, while ASTM B466 defines the alloy chemistry and mechanical requirements for general pipe and tube.
Q: Why does the alloy contain iron?
Iron in the range 1.0 - 1.8% is essential to the seawater performance of 90/10 copper nickel. It strengthens the protective surface film and gives the alloy its resistance to impingement and erosion-corrosion.
Q: What does CuNi10Fe1.6Mn mean?
The designation states the nominal composition: about 10% nickel, 1.6% iron and a controlled manganese addition, which is the 90/10 copper nickel alloy also known as UNS C70600.
Q: Can 90/10 copper nickel tube be welded?
Yes, with a matching nickel-bearing filler and low heat input. Cleanliness is critical because carbon and sulfur contamination causes cracking of copper nickel at welding temperature.
Q: How does 90/10 compare with 70/30 copper nickel?
The 70/30 alloy, UNS C71500, has higher strength and better resistance to fast-flowing seawater but costs more because of its higher nickel content, so it is reserved for the most demanding circuits.
Q: Which temper is supplied for seawater piping?
Most seawater and condenser service uses annealed tube for ductility, while light-drawn tempers are selected where higher strength is needed for a specific pressure design.
