释义 |
Mumetal|ˈmjuːmɛtəl| Also Mu-metal, and with small initial. [f. mu (µ being conventionally used to denote permeability) + metal n. (and a.).] The proprietary name of an alloy of iron that contains approximately 75–78 per cent nickel, 4– 6 per cent copper, and 1½–2 per cent chromium by weight and is a useful material for transformer cores and magnetic shields because of its high permeability and low hysteresis loss in weak magnetic fields.
1924Trade Marks Jrnl. 16 Apr. 858 Mumetal... Metallic alloys, unwrought or partly wrought. The Telegraph Construction and Maintenance Company, Limited,..London,..manufacturers. 1925Jrnl. Iron & Steel Inst. CXII. 74 The first commercial application of high-frequency melting in Europe was made by a British firm for the preparation of nickel–iron alloys for submarine cables. The research work..quickly resulted in the perfection of a series of alloys known under the name of ‘Mumetal’. 1932Discovery May 142/1 Pure iron, silicon–iron, permalloy, and mumetal are used because they can be magnetized and demagnetized without loss. 1945Electronic Engin. XVII. 384 (caption) Recorder unit showing tube enclosed in Mu-metal screen. 1966New Scientist 18 Aug. 351/3 The enclosures were formed of a material (mu-metal) which screens off the Earth's field. 1973Physics Bull. Dec. 719/2 Until now conventional recording heads have had cores of a soft magnetic material, typically ferrite or laminated mumetal. |