Implanted medical devices refer to any surgical procedure in which the device is fully or partially inserted into the human body or natural cavity, and remains in the body for a long period of time after the surgical process, or partially remains in the body for at least 30 days. These devices are considered implanted.

Implanted devices mainly include bone nails and plates, artificial joints and hearts, contact type artificial organs such as artificial skin, corneal stents, vascular stents, and esophageal stents, implantable hearing aids, and external artificial larynx and other auxiliary equipment.

Due to prolonged contact with the human body, coatings on implantable medical devices require not only low friction coefficient, wear resistance, and corrosion resistance, but also better biocompatibility. In addition, antibacterial performance is also important for ensuring the long-term use of implants. The commonly used implant materials currently include titanium alloys, cobalt chromium alloys, nickel titanium alloys, some stainless steels, and magnesium alloys. In order to better apply implant materials to the human body, coating technology is usually used to improve their surface properties.