| 摘要 |
<p>Disclosed is a polyamide powder for coating a metal surface by a fluidized-bed coating process, wherein: the powder has a median grain size d 50 of from 20 to 90 .mu.m, the powder has a content of fine particles whose median grain size is less than 5 .mu.m of below 1%, and the powder has at least 75% of spherical particles in which all three spatial axes x, y and z of the particles are within ~ 10% of the same dimension. The powder is useful in a fluidized-bed coating process, especially in producing a chromate-free coating on a steel pipe, such as pipes in automobiles.</p> |
