Porosity Measurements of Flame Sprayed Aluminum

Characterization of porosity in thermal spray coatings has continued to be an important aspect in understanding the properties of deposited materials and is critical to quality control. Al coatings deposited by flame spray could be determined using traditional micrometers, however, porosity would be included in those measurement. Effective thickness was determined to be a measure of the amount of fully dense material deposited, if porosity where to be excluded. This effective thickness results in smaller measurements relative to the apparent thickness measurement, as porosity is taken into account. This investigation determines the thickness measurement of a coating using “closed” and “open” pores vs the apparent thickness to determine the quality of a coating.

Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia LLC, a wholly owned subsidiary of Honeywell International Inc. for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA0003525.