Recently, Beijing Langqiao Surface Technology Development Co., Ltd. (LQ) developed a spherical nano zirconia ceramic powder and name it as LF441.

LF441, with good flowability, is a spherical zirconia powder stabilized by 8% Y₂O₃. In the manufacturing process, ZrO₂ of originated nano sized particles reacts with Y₂O₃ to form a solid solution of cubic and tetragonal crystal structure and then heated and densified by plasma arc. Compared with the powder made from other manufacturing processes like crushed or dry agglomerated, LF441 has the following characteristics:   

- good flowability, thus ensuring the stability of powder feeding.     

- chemical homogeneity and structural stability of the resulted coating. 

- free of impurities caused by the contamination of crushing process.

In the plasma densification process of LF441, the temperature is strictly controlled. During the powder shrinkage process, a hollow structure is formed, which is believed to be beneficial to the uniform heating of powder during spraying. The coating of LF441 powder has better thermal shock resistance and thermal cycling stress resistance than CaO and MgO stabilized ZrO₂ coating and the Y₂O₃ has a relatively longer retention time in the solid solution under high temperature and thus will not migrate to form the monoclinic phase that will destroy the structure. The Ar/H₂ or N₂/H₂ is used as working gas when spraying LF441 by plasma, while if using the ID gun, Ar/H₂ is recommended.

This product is equivalent to the competitor's product like METCO 204B-NS, and the particle size of which can be adjusted according to customer's requirement. The picture below is the photo of the particles of Langqiao’s LF441 powder.