FE-NI ALLOY HAVING HIGH STRENGTH AND LOW THERMAL EXPANSION, A SHADOW MASK MADE OF THE ALLOY, A BRAUN TUBE WITH THE SHADOW MASK, A LEAD FRAME MADE OF THE ALLOY AND A SEMICONDUCTOR ELEMENT WITH LEAD FRAME

摘要

Disclosed is an FeNi alloy consisting of, by mass, 30 to 50% of Ni (or 27 to 47% Ni and not more than 22% Co), 0.005 to 0.1% of Nb, less than 0.01% of C, 0.002 to 0.02% of N, and the balance of Fe and inevitable impurities, wherein the equation; ;is fulfilled. In the alloy, preferably, the maximum grain size of compounds primarily containing Nb and nitrogen and other compounds primarily containing Nb and C is less than 0.5 m, which can be observed at an fractional section of metal structure, and a total number of the compounds is not less than 50,000/mm² at an fractional section. An average grain size of the alloy structure is not less than 10 by the crystal grain size number as defined in JIS G0551. The alloy may applied to shadow masks for the Braun tube and lead frames for semiconductor elements.