Surface Modification of Stainless Steel for Surgical Tool by EB-Polishing

Abstract

A new surface finishing method by large-area electron beam irradiation (EB-polishing) for stainless steels for orthopedic surgical tool was proposed in our previous paper, and it was shown that high-efficient surface finishing was possible by the EB-polishing. In this report, the surface structure of EB-polished stainless steel is analyzed by TEM and EDX. Also, surface modification effects such as resistance to corrosion and blood repellency are evaluated. Then, the applicability of the EB-polishing as a new surface modification method of stainless steel for orthopedic surgical tool is discussed.

Surface modifications of a cold rolled 2024 Al alloy by high current pulsed electron beams

“…For example, the cooling rates have been calculated [9,[25][26][27]and investigated experimentally [28] to be of the order of 10 8 -10 9 K/s. Such a drastic temperature variation induces the formation of thermal stresses and shock waves reaching several hundreds of Mpa, which would induce severe surface deformation the materials [29][30][31][32][33].With repeated heating and cooling induced by successive pulsed electron beams irradiation, it has been observed that precipitates are partially or completely dissolved and that chemistry segregations are drastically reduced in the top surface melted layer where supersaturated solid solution can form [34,35].These microstructural changes improve the corrosion resistances of the surface layer which has been established in various alloys such as steels [34][35][36][37], Mg alloys [38][39][40]and Al alloys [41].Besides, due to the effect of dynamic stress fields induced by the drastic thermal processes on the material, plastic deformation occurs at the treated surface and subsurface layers, resulting in surface and subsurface microhardness enhancement [30,37,42].…”

Effect of prior laser microstructural refinement on the formation of amorphous layer in an Al86Co7.6Ce6.4 alloy

“…Large-area electron beam (LAEB) irradiation, a recent variant of electron beam treatment, has several advantages such as a large beam size (~60 mm in diameter) which decreases processing time by decreasing the need for overlapping tracks. It has been used to polish mould surfaces [7], increase hardness and wear resistance [8], lower surface roughness, reduce the porosity of sprayed coatings [9] and, as demonstrated in our previous paper [10], generate an amorphous layer when used to melt the surface of a cast Al-Co-Ce alloy. However, cracking of the amorphous layers was found to occur around large, pre-existing particles of the Al 8 Co 2 Ce phase.…”