An innovative spacecraft manufacturer used composite materials for a structural component of their ship. These composite components were manually prepared and bonded together.  The company lacked an accurate, quantifiable, objective and in-line method to monitor the surface treatment process.

The manufacturer utilized a surface preparation method that included a solvent wipe, hand sanding, and a final solvent wipe. This manual process left plenty of room for human error and lacked the ability to measure and monitor consistency, allowing for uncertainty and potential for failure and re-work.

The spacecraft manufacturer sent a sample of their material component to BTG’s Materials and Processing Lab where the company’s M&P Engineers used the Surface Analyst to examine their process step-by-step.

Three contact angle measurements were taken on four areas of the part. The first measurement was on the as-received sample; the second, after the first solvent wipe; and the third was taken after the sanding and final solvent wipe. While the contact angle varied slightly at each measurement point, the trend was a decrease in contact angle throughout the process. The Surface Analyst showed the sample’s increase in surface energy through the preparation process.

BTG Labs was then able to help the manufacturer determine contact angle pass/fail parameters that could be loaded into the Surface Analyst, allowing the surface preparation process to seamlessly flow on the manufacturing floor.

Composite preparation process monitored with the Surface Analyst. Final contact angles correlate to bond strength required for this application. Contact angle parameters can vary depending on application.