Lastek 501

Welding CuNi 90/10

Alloy for TIG welding of copper-nickel alloys with 10 % nickel.

High corrosion and erosion resistance in seawater.

Porous free welds, with high toughness.

Specifications & Usage


Heat exchangers for marine, power, chemical, petrochemical service, condensers, evaporators, coolers, radiators.

Assembling piping sections for salt water circulation aboard ships.

Welding alloy C70600, Cunifer 10.


Always thoroughly remove oil and grease, marking crayons and cutting lubricants as those elements could create hot intergranular cracking under high restraint. Also remove mill scale or oxides on the surface by brushing with a stainless brush.

If thickness is less than 3 mm prepare the edges square; when higher than 3 mm use a single V with 80° included angle.

We recommend Lastek 503 (higher strength) for sections thicker than 3 mm in copper nickel 90/10, although Lastek 503 is more prone to hot cracking in presence of contaminants and has a higher melting temperature.

Grooved copper bars on the underside can help to control penetration.

No preheat or post heat treatment is required.


Welding proces: Tig welding (GTAW)
Material Type: Copper (alloys)
Welding positions: NA
Norm : EN ISO 24373
Classification: CuNi10 - Cu 7061
Minimum packing: 5 kg in a cardboard box