| 摘要 |
846,981. Magnetic compositions. KIKUCHI, Y. Feb. 13, 1958 [Feb. 16, 1957], No. 4817/58. Drawings to Specification. Class 38 (2). A ferromagnetic material suitable for a magnetostriction vibrator is made by pulverizing and mixing together 0.5 to 65 mol. per cent of copper oxide, 0.1 to 68 mol. per cent of nickel oxide, 0.1 to 20 mol. per cent of cobalt oxide and 30 to 60 mol. per cent of ferric oxide, presintering the mixture at 1000‹ C., repulverizing, moulding, sintering at between 900‹ C. and 1400‹ C. for ¢ to 3 hours in oxygen, and cooling at 5‹ to 10‹ C. per minute. Curves are given showing the variation of the electromechanical coupling factor, magnetostriction saturation characteristic and the temperature coefficient of mechanical resonant frequency with different values of sintering temperature and of x and y when the composition can be represented by the formula |
