CERTIFICATIONS
Material Creation Projects
British manufacturer Copper Alloys Ltd revolutionises the art of marine forgings.
What was the project?
For marine applicati ons, engineers have long been aware of the limitations in corrosion resistance of Aluminium Bronzes and steels, especially for applications requiring extreme performance over an extended life time.
Typically this issue has been managed by a twin approach of:
1. Designing thicker sectionsto allow for corrosion
2. Replacing components at intervals throughout the life time
Clearly both options are sub-optimal as they do not address the root cause of the problem. To address this, the Ministry of Defence commissioned trials to try to forge a copper-nickel-chrome alloy [DEF STAN 02 824], which had only previously been produced in a cast and very limited closed die forged condition.
Compared to aluminium bronze, copper-nickel-chrome is in general ten times more corrosion resistant and is five times more resistant to shock, with comparable cost (see overleaf ).
In the early 1990s, extensive funding was given to forging companies to make a batch of wrought copper-nickel-chrome. The trials were a disaster, with billets breaking up on forging. Despite the support, the companies at the time failed and gave up. As a result the Ministry of Defence abandoned the project.
You achieved what I thought was impossible
Senior Metallurgist, Ministry of Defence
About Copper Alloys Ltd
- Specialist metal producer in Stoke-on-Trent, England
- Producing speciality metals and components for critical engineering applications
Project Goals
- Create the ultimate alloy for nuclear submarines
- Engage with end users to steer innovation
- Develop process technology to standardise production and reduce cost
Approach
- The application of deep knowhow from previous alloy development
- Enhanced foundry control to ensure forgeability
- Provide formats suitable for use in the marine
Results
- Genuine new mater ial technology
- Enhanced options for design authorities
- Customer “you achieved the impossible”
An elegant solution
The technical control and process technology developed at Copper Alloys Ltd in order to successfully deliver previous complex alloy development over previous years was put to good use. The unique knowhow of melting, alloying, casting and combined with forging parameters, were key to creating high integrity forgings in copper-nickel-chrome.
Material creation
The development was successful, enabling Copper Alloys Ltd to identify reliable process routes and offer wrought copper-nickel-chrome in a comprehensive range of formats including blocks, rings, discs, bars and customised sections within a 5,000kg envelope.
Wrought CNC structure etched 100x magnification grain size around 45μm.pngThe next generation of marine alloys
This range of copper-nickel alloys represents the first genuine new material technology for the marine defence industry in years. It is offered as one of three Elite Marine Alloys, which present design authorities with an innovative approach to through-life cost saving and enhanced performance.
United Kingdom