Rapid quenching of aluminium fabrications

Citation

(2000), "Rapid quenching of aluminium fabrications", Aircraft Engineering and Aerospace Technology, Vol. 72 No. 6. https://doi.org/10.1108/aeat.2000.12772fab.004

Rapid quenching of aluminium fabrications

Rapid quenching of aluminium fabrications

Keywords: Carbolite, JS Chinn, Ovens, Aluminium, Fuselage

A specially designed carbolite oven is said to be enabling JS Chinn Ltd to provide solution treatment of thin aluminium alloy panels with minimal temperature loss between the heating cycle and quenching (Plate 5).

JS Chinn, a specialist manufacturer of aircraft fuselage fabrications, ordered the oven to enable it to process a wide variety of skin panels up to a maximum size of 3m x 2m. As the maximum thickness of the material is only 1.6mm, it has to be quenched within five seconds of leaving the oven, to ensure the metallurgical characteristics are retained.

The oven is also used by JS Chinn for annealing and precipitation without quenching.

The oven stands on a gantry about two metres above floor level, while the quench tank and loading/unloading station are at floor level. The oven travels on the gantry to the correct position, as required. Work to be treated is loaded into a stainless steel basket designed to accept panels of various sizes, which is then hoisted into the oven. A typical charge weighs 80kg.

Plate 5 JS Chinn Ltd's specially designed carbolite oven

A solution treating cycle generally lasts one hour at a temperature of 500°C. Effective air circulation is provided by eight heavy-duty fan impellers and air guides, which give a vertical air flow through the chamber from bottom to top. Temperature uniformity is nominally rated at ±3°C.

If solution treatment is being carried out, the oven is positioned above the quench tank and the work basket is lowered into it directly from the heating chamber. For annealing and precipitation processes, the basket is lowered on to the loading/unloading bay to cool in air.

Details available from Carbolite. Tel: +44 (0) 1433 620011; Fax: +44 (0) 1433 621198.