The FeNi alloy and its production manner null which are superior in contact print prevention Characteristic and gas radiation Characteristic at the time

摘要

PURPOSE: To produce an Fe-Ni alloy sheet suitable for shadow mask in high yield by specifying the heating atmosphere, heating temp., and holding time at the time of slabbing and the Si segregation rate at the surface of a steel sheet, respectively, at the time of producing a sheet from an Fe-Ni alloy slab with a specific composition. ;CONSTITUTION: Heating at the time of slabbing an alloy having a composition which contains, by weight, 34-38% Ni, 0.01-0.09% Si, 0.002-0.020% Al, 0.0002-0.0020% Ca, and 0.0003-0.0020% Mg and also contains impurities in the form of CaO-Al₂O₃-MgO type metallic inclusions having ≥1600°C melting point and ≤6μm grain size by ≤0.004% expressed in terms of oxygen and where the value of Ca+Mg/2 is regulated to 0.0005-0.0025% is done by performing heating and holding in an atmosphere having ≤100ppm H₂S concentration at a temp. of T°C in the range between 1150 and 1300°C for a time(t) represented by inequalities I, II and then exerting slabbing at reductions of area of ≥35% and 20-70%. Subsequently, the Si segregation rate represented by equation III at the surface of a sheet produced by means of hot rolling and cold rolling is regulated to ≤10%, by which the Fe-Ni alloy sheet suitable for shadow mask can be produced.;COPYRIGHT: (C)1993,JPO&Japio