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In order to achieve high efficiency, energy saving and high quality of welding, it is necessary to carry out research on cable-type wire TIG-MIG hybrid welding. In this study, voltage and current influences on the arc shape in cable-type wire TIG-MIG hybrid welding were studied. The results showed that in cable-type wire TIG-MIG hybrid welding, with an increase in the TIG current, the MIG current increased at first and then remained constant, while the MIG basic voltage remained unchanged. With an increase in the MIG voltage, the TIG current produced small changes, but overall, it remained stable. The TIG current of different droplet-transfer modes had different effects.

Lead zirconate titanate (PZT) particles with pure tetragonal structure were synthesized by solid-state reaction method and used for preparation of slurries with different solid contents (34-80 wt.%). Then, PZT thick films were fabricated by the nonaqueous tape casting method. It was shown that the slurry prepared from ball-milled particles exhibited better rheology properties than slurry from particles which were not ball-milled. Measurement of sedimentation volumes and zeta potentials indicated particle aggregation, resulting in weak stability of the slurries with high solid contents. The microstructure, piezoelectric and ferroelectric properties of PZT sintered films were investigated in terms of solid contents. Ceramic films prepared from the slurry with solid contents of 73 wt.% had the optimal structure and properties. After poling at 200 ?C with an applied field of 1.2 kV/cm, a d33 of 294 pC/N was achieved; typical ferroelectric properties were also observed with a Ps of 38 ?C/cm2.