New magnetic alloys for magnetic recording heads

A study was made of the magnetic and mechanical properties of the alloys obtained by adding titanium and niobium to 4Mo-79Ni Permalloy. The mechanical hardness markedly increases with the addition of titanium, being about 240 in Vicker's hardness at 3% titanium, and about 300 at 3.5% titanium. One of the new alloys has μe= 12000 (0.22 mm, 1 kHz), Hc = 0.01 Oe, B10= 5000 G, and ρ = 98 μΩ cm at the composition of 3% Ti-2.8% Nb-3.8% Mo-10.5% Fe-0.5% Mn-balance Ni. Moreover, it is supposed that this alloy is hardened not only by solid solution hardening, but also by precipitation hardening because the coercive force decreases as hardness increases at the initial stage of hardening.