Change of Electroless Ni-Mo-P Alloy Films by Transient Pulse Heating

The change of electroless Ni-Mo-P alloy films was investigated using a pulse heating method that provided a very high heating rate (up to 10⁶ K min^-1) and a very short heating time (200 ms). Both amorphous and crystalline Ni-Mo-P alloy films under “as-plated” conditions were prepared by controlling the Na₂Mo0₄ concentration in the plating baths. The heat change properties of both amorphous and crystalline films during the pulse heating were compared with those during conventional long-time annealing, by measuring the specific resistance, the temperature coefficient of resistance, and the saturation magnetization. For both amorphous and crystalline Ni-Mo-P alloy films under “as-plated” conditions, the crystallization and the phase transformation processes which occurred during the pulse heating were different from the corresponding processes observed in the conventionally annealed films. Furthermore, the film structure after the higher-power pulse heating was also found to be different from that after conventional annealing at 700°C for lh. The Ni-Mo-P alloy film after the pulse heating was very stable against change in the later conventional annealing at 700°C for lh.