The rectification of defects by welding is not permitted on Class 1 and Class 2 forgings.
They do not experience chloride or sulphide stress corrosion. They have a high resistance to ammonia stress corrosion compared to other copper alloys and do not require a stress relief anneal for seawater service.
They are available but 70-30 copper-nickel consumables are preferred for welding both the 90-10 and 70-30 alloys due to superior deposition characteristics.
Copper-nickel alloys can harbour slimes, but the attachment of macro-organisms—such as marine grasses and shellfish—is impaired. If these do become attached under quiet conditions, adherence is poor and they can be easily removed mechanically.
This publication provides an understanding of the two primary copper-nickel alloys to allow good fabrication and operational practices to optimise in-service performance. Topics covered include general engineering properties of 90/10 and 70/30 copper-nickels, welding and fabrication practices and a basic overview of corrosion and performance in seawater immersion trials. 2018. 32pp.
The aim of this publication is to provide engineers with an appreciation of copper alloys commonly used in marine applications. It will provide an overview of the range of alloys and their properties, and give references and sources for further information. 2018. 32pp.
Copper alloys can harbour slimes, but the attachment of macro-organisms—such as marine grasses and shellfish—is impaired. If these do become attached under quiet conditions, adherence is poor and they can be easily removed mechanically. Copper alloy mesh prolongs the intervals between periodic cleaning, thus promoting a cleaner and healthier environment for aquaculture.
Practical guidance for engineers wishing to specify, design or produce nickel aluminium bronze components for marine, aerospace and other sectors. 2018. 100 pp.
Corrosion of copper alloys in seawater can be mitigated. This publication offers practical guidance on alloy selection, design and preventative measures and has been written principally for marine, mechanical and other engineers who have to select materials of construction but do not have a corrosion background. 2018. 20 pp.
Yes they can be brazed by all processes. Appropriate silver brazing alloys should be used as phosphorus bearing brazing alloys cause a reaction with nickel to form a brittle phosphide phase.
Yes they can using appropriate 65% nickel-copper consumables to avoid iron dilution effects.
This book, commissioned by CDA, updates information contained in the standard reference work by P J Macken and A A Smith, published in 1966. It contains valuable new material on the metallurgy of aluminium bronzes, the composition and manufacturing conditions required to ensure reliable corrosion resistance – also, alloying elements, physical properties, casting processes, properties of castings, manufacture and design of castings. 1999. 434pp.