The critical surface tension of 316L stainless steel.

摘要

Thrombogenicity (surface induced blood-clotting) is a major issue with metallic stent implant-devices. Although the exact causes for this are unclear, it is thought that several surface properties are responsible. In this study the critical surface tension of 316L stainless steel was investigated, as a function of surface treatments and plastic strain. The critical surface tension, which is related to the solid's surface tension, has been shown in previous work to correlate with the thrombogenicity of implant materials.; Using the Zisman technique to analyze contact angle data, obtained from sessile drop measurements, the critical surface tension was determined. It was found that the surface treatment consisting of electropolishing, followed by passivation for 30 minutes in 30% nitric acid, resulted in the only surface that lied within the previously established range of biocompatibility. Additionally, surface strain up to 30% did not result in a significant change to the critical surface tension.