Application of the newly developed technology in stainless steel for biomedical implant

摘要

The present invention pertains to a method of applying surface mechanical attrition treatment (SMAT) with a plurality of balls for treating surfaces of metallic alloys under a set of specific conditions in order to obtain a metal substrate with high yield strength and hardness, low cytotoxicity, high cytocompability and hemocompatibility suitable for medical implant. The plurality of balls used in the present invention comprises 316L stainless steel balls or zirconium oxide (ZrO2) balls.

主权项

1. A method for treating a medical implant, the method comprising:
applying surface mechanical attrition treatment (SMAT) with a plurality of zirconium oxide (ZrO2) balls on surfaces of a stainless steel based substrate of the medical implant; and providing an enclosure with a chamber for holding said substrate on one side of the chamber and a vibrating means on opposite side to said substrate; wherein said vibrating means is configured to vibrate in a frequency and amplitude to move said plurality of ZrO2 balls along the chambers towards said substrate such that the plurality of ZrO2 balls being moved back and forth inside the chamber is capable of treating the surfaces of said stainless steel based substrate within a treatment scheme to improve cytocompatibility and hemocompatibility of the medical implant; wherein treatment of said substrate by plasma nitriding is avoided; and wherein the treatment scheme comprises a total treatment time of about 30 minutes for treating two surfaces of the stainless steel based substrate, said total treatment time being divided into four time intervals comprising:
a. from 0 to 1st minute: 5 seconds per strike on each surface of the substrate;b. from 1st to 5th minute: 10 seconds per strike on each surface of the substrate;c. from 5th to 29th minute: 15 seconds per strike on each surface of the substrate;d. from 29th to 30th minute: 10 seconds per strike for 2 times on each surface followed by 5 seconds per strike for 2 times on each surface of the substrate.