Mechanical properties of inorganic biomedical thin films and their corresponding testing methods

Coatings on implants are aimed to achieve some or all of the improvements in abrasion, corrosion resistance, metal ion release protection, increased bioactivity, biocompatibility, and ultimately an improved environment and structure for new bone attachment. Adhesion, mechanical properties and testing methods are used to determine the viability of coated implants or devices and their performance under simulated physiological environments. Perforation or delamination of the coatings can expose the substrate to accelerated wear or corrosion, and the released coating particles may act to accelerate third party wear resulting in a negative host response. An in-depth understanding of the adhesion of the implants and the susceptibility of the coating to cracking and delamination are critical important reliability issues. The aim of this review is to give a brief description on the various techniques used to produce micro and nanocoatings currently used or being investigated within the biomedical field. This is followed by an overview of some of the most widely used test methods for measuring mechanical properties and adhesion performance of coatings used in medical applications.

► Techniques developed to determine mechanical properties of biomedical thin films are highlighted.
► The mechanical properties of various biomedical thin films coatings are discussed.
► Challenges and crucial issues with regard to testing mechanical properties of biomedical coatings are highlighted.
► The latest achievements in HAp coated implants are discussed.