Page 36 - PCMI Journal July 2018

David Allen | Emeritus Professor | Cranfield University | UK Photochemical Machining of Aerospace Materials
5/31/18
Aluminium and its alloys
Aluminium alloy designation
Composition
1100 series
(essentially pure aluminium)
99.6% min. Al
6061
Major alloying elements (by max %wt.) include Mg 1.2%, Si 0.8%, Fe 0.7%, Cu 0.40%, Mn 0.15%, remainder Al
5052
97.2% Al, 2.5% Mn, 0.25% Cr by weight
Alfenol
(magnetically soft iron alloy)
12% Al - Fe 16% Al - Fe
Limitations of machining aluminium
• Reflection of laser beam can compromise laser cutting performance
• Punching can be unreliable as aluminium has a tendency to coat dies
• Stresses and burrs common with conventional machining techniques
• CNC machining can be effective, but costly!
Issue 131 July 2018 PCMI Journal 35
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