Superconducting Properties of Thick Films on Hastelloy Prepared by the Aerosol Deposition Method With Ex Situ MgB2 Powder

We present a new high-deposition-rate coating technique that allows us to produce at room temperature long thick films of MgB 2 on flexible steel substrates. Such a technique might give rise to new tapes with higher filling factors compared to the standard processed tapes. With the so-called aerosol deposition technique, MgB 2 films were prepared on Hastelloy substrates with commercially available ex situ-prepared MgB 2 powder (T C,onset of 38 K, JC of 3.8·10 3 A/cm 2 at 4 K and 1 T). Microscopic analyses yield nanocrystalline dense films with high film stresses. The as-deposited films have so far a superconducting transition temperature T C0 of 18.1 K and a critical current density J C up to 5·10 3 A/cm 2 at 4 K and self-field obtained.