Microstructure and Mechanical Properties of Zinc Matrix Biodegradable Composites Reinforced by Graphene

Abstract

This work used spark plasma sintering (SPS) to prepare graphene nanosheets (GNS) reinforced zinc matrix composites. The influence of GNS on the microstructure and mechanical properties of zinc matrix composites was studied. The results show that the GNS/Zn composites prepared by SPS have a dense structure and good interface bonding, and GNS are uniformly distributed in the zinc matrix. Adding GNS can significantly improve the mechanical properties of the zinc matrix. When 0.7 wt% GNS are added, the comprehensive mechanical properties of the composite material are improved. The ultimate tensile strength is 254 MPa, and the Vickers hardness is 65 HV, which are 126 and 20.3% higher than those of pure zinc (112 MPa and 54 HV), respectively. The strengthening mechanisms of GNS/Zn composites are mainly load transfer of GNS and dislocation strengthening caused by coefficient of thermal expansion (CTE) mismatch. In addition, the biodegradability of GNS/Zn composites was evaluated by electrochemical measurement and immersion test. The results show that adding GNS to the zinc matrix will accelerate the degradation rate of the composite material. But the degradation rate can be controlled by the content of GNS. Its degradation rate is in the range of 69–301 μm/a, an ideal degradation rate as an orthopedic implant material.

Gas phase synthesis and adsorption properties of a 3D ZIF-8 CNT composite

“…3A) comprises one component located around 283.7 eV (black peak) which can be attributed to an inorganic zinc carbon environment. 35 The strong peak at 285 eV corresponds to a hydrocarbon contamination (C-C/C-H) and the peaks centred at 286.4 eV and at 289 eV are due to mono and bi oxygenated carbon environments. The O 1s spectrum of the ZnO@VACNT sample consist of two main peaks (Fig.…”

Mechanical Properties, Degradation Behavior, and Cytocompatibility of Zn–Mg–Graphene Nanoplatelets Composite for Orthopedic‐Implant Applications

“…Another effective way to attain better mechanical properties for Zn‐based materials is the fabrication of metal matrix composites (MMCs) by choosing a suitable reinforcement and processing technique, as smaller alloy additions (<1 wt%) of nano‐reinforcement can change the microstructures resulting in improved mechanical as well as corrosion properties of MMCs. [ 42,43 ] Zn‐based MMCs are usually reinforced with bio‐ceramics, such as hydroxyapatite, [ 44,45 ] tricalcium phosphate (TCP), [ 46 ] tungsten carbide, [ 47 ] monetite, [ 48 ] silicon carbide (SiC), [ 49 ] and titanium diboride. [ 50 ] Yang et al [ 44 ] reported a reduction in ultimate compressive strength ( σ UCS ), while improvement in biocompatibility upon the addition of hydroxyapatite in pure Zn.…”

“…Yang et al [ 63 ] reported the homogeneous distribution of rGO in the pure Zn matrix without the formation of any intermetallic compounds, leading to an improvement in the mechanical strength of Zn matrices. In another study, Dai et al [ 42 ] fabricated graphene nanosheet‐reinforced ZMCs via spark plasma sintering, and their results showed that the addition of 0.7 wt% graphene increased the σ UTS and MH of pure Zn by 126% and 20%, respectively. Nonetheless, the reported values of the mechanical properties were still below the desired values for load‐bearing implant materials.…”

Biodegradable zinc‐based materials with a polymer coating designed for biomedical applications

“…However, polymeric and bioceramic materials do not provide the necessary mechanical support for damaged bones in weight‐bearing applications 4,7,9 . Moreover, metals can be easily handled by common methods, such as powder metallurgy, machining, forming and casting 4,7,9,10 . On the other hand, metallic materials exhibit suitable mechanical properties but are not osteogenically active.…”

“…Non‐degradable metallic biomaterials, such as cobalt‐chromium alloys (Co‐Cr‐Mo), titanium alloys (Ti, Ti‐Al‐V, Ti‐Al‐Nb), super elastic Ni‐Ti and stainless steels (SS), are currently used primarily for permanent implants to maintain load‐bearing hard tissue function by providing mechanical support 3,7–13 . These metallic materials possess a high corrosion resistance to human‐body fluids.…”