Effect of temperature, humidity and crystal directions on wear of rotary heads

In the advanced tape drive systems which achieve a higher recording density, the wear of rotary heads should be decreased to obtain a higher reproduced output signal by decreasing the ‘Gap depth’ of heads, keeping enough life time. By using the heads made by two kinds of crystal directions of Mn–Zn ferrite and metal evaporated tapes with DLC coating, temperature and humidity dependences of head wear are investigated. The wear rates of both crystal direction heads increase with the decrease in temperature. The wear rate of a (110) head increases very quickly at low temperature, compared with a (100) head. These temperature dependences of head wear are caused by the temperature dependence of the elastic modulus of the tape and the temperature dependence of the friction coefficient between the tape and the head.