Kynal

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Kynal was a brand name for a series of aluminium alloys developed and originally produced by the British chemical manufacturer Imperial Chemical Industries (ICI). [1] The name was derived from Kynoch, an existing ICI trademark for ammunition, and aluminium. It was largely used as substitute for Alclad, a popular corrosion-resistant aluminium alloy.

Contents

ICI produced Kynal in quantity at a facility in Waunarlwydd, outside Swansea. The material was extensively used by the British aviation industry during the Second World War, being recognised as a strategic resource. Numerous variations upon the material were devised by ICI around this time. During the 1950s, British Railways became a key consumer of Kynal, using the material on numerous members of its new fleet of diesel traction, including the first generation diesel multiple units (DMUs). By the twenty-first century, the material was largely considered to be obsolete, while the Waunarlwydd chemical works was permanently closed during the 2000s.

History

A key facility involved in the production of Kynal was the Ministry of Aircraft Production's factory at Waunarlwydd, [2] near Swansea. ICI built and operated the plant on the government's behalf. [3] Functionally, Kynal was similar to, and could be a substitute for, Alclad. [4] Applications included various forged items, including pipework, vessels, and heat exchangers, as well as fuselage elements of aircraft. [5] [6] By 1938, the material was being producing at a very high volume as a consequence of the European powers having entered a period of rearmament around the time of Munich crisis, which led into the Second World War. [7]

During the postwar era, Kynal continued to hold its strategic importance. [8] The material proliferated throughout British engineering throughout the 1950s and 1960s; it began to be used in the frames of road vehicles during the mid 1950s. [9] Kynal was used extensively for British Railways' modernisation of the 1950s, specifically in the construction of the publicly-owned organisation's new diesel fleet. [10] The majority of the 'lightweight' diesel multiple units (DMUs) featured the material. [11] Around the same era, the company was also involved in studies into the use of Kynal as a roofing material. [12]

By the twenty-first century, Kynal was largely considered to be obsolete as a material. [13] During the 2000s, the original Waunarlwydd plant, which was by then owned by Alcoa, was closed down. [14] [15] Despite this, research efforts into fields such as battery technology have involved the use of Kynal. [16]

Table

Al Cu Mg Si Mn Ni Zn Others
 %
Kynal P5≥99.5Pure aluminium [17]
Kynal P10≥99
Aluminium–silicon alloys
Kynal PA1512Brazing wire [18] [19]
Kynal PA165
Kynal PA175
Aluminium–manganese alloys
Kynal PA191.25 [20]
Aluminium–magnesium alloys
Kynal M35/12 [21]
Kynal M35/23
Kynal M365
Kynal M377
Aluminium–magnesium–silicon alloys
Kynal M39/10.70.5 [22]
Kynal M39/20.71
Aluminium–copper alloys
Kynal 902.20.3 [23]
Kynal C6540.60.5 [23]
Kynal C664.40.60.70.6
Kynal C674.40.60.70.6
Kynal C6911 [22]
Nickel–aluminium alloys
Kynal Y882.61110.1% Ti [23]
Kynal Y9241.52
Aluminium–zinc alloys
Kynal Z930.42.75.3 [24]
Kynal-Core C65A Pure aluminium-clad forms of the corresponding alloys [25]
Kynal-Core C66A
Kynal-Core C67A
Kynal-Core C68A
Kynal-Core Z93A

See also

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References

Citations

  1. ↑ "ICI Metals Division". Grace's Guide .
  2. ↑ 51°38′41″N4°01′16″W / 51.644727°N 4.021163°W
  3. ↑ "ICI Metal Works; Alcoa Aluminium Factory, Waunarlwydd, Gowerton". Coflein .
  4. ↑ Ross 2013, p. 50.
  5. ↑ J. H. Argyris; S. Kelsey (1 May 1959). "The Analysis of Fuselages of Arbitrary Cross-section and Taper: A DSIR Sponsored Research Programme on the Development and Application of the Matrix Force Method and the Digital Computer". Aircraft Engineering and Aerospace Technology. 31 (5): 133–143. doi:10.1108/eb033113. ISSN   0002-2667.
  6. ↑ "Curtailing Corrosion in Chemical and Petroleum Engineering". Anti-Corrosion Methods and Materials. 5 (6): 195–196. 1 August 1958. doi:10.1108/eb019457. ISSN   0003-5599.
  7. ↑ "ICI Advertisement". Flight . 9 June 1938. p. 14.
  8. ↑ "The British Light-alloy Industry". Flight . 10 June 1955. pp. 808–811.
  9. ↑ "Kynal lightens". The Automobile Engineer. 1956. p. 125.
  10. ↑ Carter, R. S. (1963). "North British Locomotive Co. diesel-hydraulic B-B Type 2 (British Rail Class 22)". British Railways Main-Line Diesels. Ian Allan Publishing. pp. 28–29.
  11. ↑ "Going Ahead with 'Kynal'". Grace's Guide .
  12. ↑ Kynal , p. 173, at Google Books
  13. ↑ Ross 2013, pp. 9, 50.
  14. ↑ "Jobs cut at metal plant". BBC News . 21 January 2003.
  15. ↑ "298 jobs to go as factory shuts". BBC News . 21 November 2006.
  16. ↑ "JP3363910B2: Non-aqueous thin battery". Google =. 1998.
  17. ↑ Metallic Materials Specification, p. 9.
  18. ↑ Metallic Materials Specification, p. 17.
  19. ↑ 'Kynal' Solders and 'Kynal' Flux for Soldering Aluminium. ICI. 1953.
  20. ↑ Metallic Materials Specification, p. 12.
  21. ↑ Metallic Materials Specification, p. 26.
  22. 1 2 Metallic Materials Specification, p. 34.
  23. 1 2 3 Metallic Materials Specification, p. 41.
  24. ↑ Metallic Materials Specification, p. 47.
  25. ↑ Metallic Materials Specification, p. 50.

Bibliography

  • Ross, R. B. (2013). Metallic Materials Specification Handbook (4 ed.). Springer Science & Business Media. ISBN   9781461534822.
  • Frick, John P., ed. (2000). Woldman's Engineering Alloys. Materials data series. ASM International. pp. 667–668. ISBN   9780871706911.
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