http://content.stockpr.com/amedica/db/265/827/pdf/paperg.pdf

Orthopedic applications of silicon nitride ceramics.

Advanced bioceramics have played integral roles in treatment modalities for damaged or diseased human joints and osseous defects. This paper reviews the uses and properties of ceramics and ceramic coatings variously employed as articulation devices in hip, knee, shoulder, and other joints, either as self-mated surfaces, or against polyethylene (both conventional and highly cross-linked versions), or for osseous- fixation as arthrodesis devices, bone scaffolds, and substitutes in the spine or extremities. The modern uses of oxide and non-oxide materials in these applications will be discussed, followed by an assessment and comparison of their mechanical and physicochemical properties. Recent developments in new bioceramic materials and composites along with advanced processing and testing methods are presented. Advanced bioceramics and coatings are expected to have increasing use in orthopaedics because of their unique combination and range of properties including strength and toughness, hardness and wear resistance, biocompatibility, bacteriostasis, and osseointegration.

Ceramics and Ceramic Coatings in Orthopaedics

Friction and wear behavior of Ni–P coated Si3N4 reinforced Al6061 composites

Cr–Al–N, Cr–Si–N, Cr–Al–Si–N coatings were successfully deposited on WC–Co substrates by a hybrid coating system combining an arc ion plating technique using Cr target, and a magnetron sputtering method using Al and Si targets under N 2 /Ar atmosphere. XRD, HRTEM, and XPS analyses revealed that the synthesized Cr–Al–N coatings consisted of solid-solution (Cr,Al)N crystallites, and the Cr–Si–N and Cr–Al–Si–N coatings with Si content of ∼ 9 at.% were fine composites consisting of (Cr,Si)N and (Cr,Al,Si)N crystallites, respectively, embedded in an amorphous Si 3 N 4 /SiO 2 matrix. The hardness values of the Cr–Si–N (∼ 35 GPa) and the Cr–Al–Si–N (∼ 55 GPa) coatings were significantly increased compared with those of CrN (∼ 23 GPa) and Cr–Al–N (∼ 25 GPa) coatings. Besides, the average friction coefficients of the Cr–Si–N (∼ 0.30) and the Cr–Al–Si–N (∼ 0.57) coatings with Si content of about 9 at.% were largely decreased compared with those of CrN (∼ 0.50) and Cr–Al–N (∼ 0.84) coatings. A comparative study on microstructural characteristics among Cr–Al–N, Cr–Si–N, and Cr–Al–Si–N coatings is reported in this paper.

Microstructures, mechanical properties, and tribological behaviors of Cr–Al–N, Cr–Si–N, and Cr–Al–Si–N coatings by a hybrid coating system

A new method for Ti–Si–N hard coatings, a hybrid coating system of arc ion plating (AIP) and sputtering techniques is introduced in this paper. Deposition behavior and mechanical properties of Ti–Si–N by the hybrid coating technique were investigated in this work. The Ti–Si–N coating layers were deposited on SKD11 steel substrates using the hybrid system where TiN was deposited by AIP method while Si was incorporated by sputtering technique. By this method, very dense and adherent Ti–Si–N coating layers could be synthesized, and the coatings were characterized by a composite consisting of fine TiN crystallites and amorphous silicon nitride. The coating layer showed the maximum hardness of 45 GPa with a load of 25 g at the Si content of 7.7 at.%. Surface roughness of the Ti–Si–N coating layer decreased with increase of Si content. The friction coefficient of Ti–Si–N layers against steel was also dependent on the Si content.

Superhard Ti–Si–N coatings by a hybrid system of arc ion plating and sputtering techniques ☆

Friction and wear properties of silicon nitride were investigated using ball-on-disk tribometer under various relative humidity levels (RHL). Friction tests were conducted against various metals (copper, nickel, titanium, aluminium). The results show that the influence of humidity depends on the material of the couples. Tribological behaviour of silicon nitride sliding on very reactive metals such as titanium and aluminium is not influenced by RHL. In contrast, the friction coefficient and wear mechanism of nickel and copper are strongly affected by adsorbed films of water vapour. Tribological properties of Si 3 N 4 /Si 3 N 4 couple were also studied and the effect of humidity was analyzed.

The wear characteristics of silicon nitride

We investigated adhesion and tribological properties of TiN and TiCN coatings prepared by physical vapour deposition (PVD) on an HSS steel substrate. Adhesion was studied by scratch test while the tribological properties were investigated using a pin-on-disk tribometer. TiCN shows higher adhesion to substrate and better wear resistance than TiN.

H. Houmid-Bennani

Papers

The wear characteristics of silicon nitride

Adhesion and wear resistance of thin hard coatings