Microstructures, mechanical, and biological properties of a novel Ti-6V-4V/zinc surface nanocomposite prepared by friction stir processing

Abstract

BackgroundThe interaction between the material and the organism affects the survival rate of the orthopedic or dental implant in vivo. Friction stir processing (FSP) is considered a new solid-state processing technology for surface modification.PurposeThis study aims to strengthen the surface mechanical properties and promote the osteogenic capacity of the biomaterial by constructing a Ti-6Al-4V (TC4)/zinc (Zn) surface nanocomposites through FSP.MethodsFSP was used to modify the surface of TC4. The microstructures and mechanical properties were analyzed by scanning electron microscopy, transmission electron microscopy, nanoindentation and Vickers hardness. The biological properties of the modified surface were evaluated by the in vitro and in vivo study.ResultsThe results showed that nanocrystalline and numerous β regions, grain boundary α phase, coarser acicular α phase and finer acicular martensite α′ appeared because of the severe plastic deformation caused by FSP, resulting in a decreased elastic modulus and an increased surface hardness. With the addition of Zn particles and the enhancement of hydrophilicity, the biocompatibility was greatly improved in terms of cell adhesion and proliferation. The in vitro osteogenic differentiation of rat bone marrow stromal cells and rapid in vivo osseointegration were enhanced on the novel TC4/Zn metal matrix nanocomposite surface.ConclusionThese findings suggest that this novel TC4/Zn surface nanocomposite achieved by FSP has significantly improved mechanical properties and biocompatibility, in addition to promoting osseointegration and thus has potential for dental and orthopedic applications.

Gradient Microstructures and Mechanical Properties of Ti-6Al-4V/Zn Composite Prepared by Friction Stir Processing

“…As seen in Figure 2b–d, the microstructures of samples mainly contain β phase regions (indicated by white dashed line). Magnified images (not shown) clearly show that the composite displays similar microstructures to the composite prepared at a traverse speed of 50 mm/min and a rotation rate of 300 rpm, which has been reported in our previous investigation [29]. However, it should be noted that the grain size of β region in the TC4/Zn composite increases with the increasing rotation rate, which are 10~15, 25~30, and 35~45 μm for the FSP225, FSP300, and FSP375 samples, respectively (Figure 2b–d).…”

Multi-Scale Surface Treatments of Titanium Implants for Rapid Osseointegration: A Review

“…However, the bio-inertness of Ti alloys leads to an extended osseointegration time with bone. In order to overcome this limitation, surface treatment technologies can be used to attain bioactive surfaces on Ti substrates [ 40 , 41 , 42 , 43 ]. The macro-scale, micro-scale, and nano-scale morphology of the implant surfaces have a crucial influence on the early bone formation and fixation [ 16 , 44 , 45 ].…”

“…Most titanium implant surfaces with certain roughness characteristics were fabricated through mixed technologies (e.g., grit-blasting, acid-etching). In addition, the latest research literature concentrates on macro-, micro-, and nano-scale surface modification through different methods with promoted osseointegration responses [ 42 , 46 , 47 ]. Meanwhile, the multi-scaled morphologies enhance protein adsorption and stimulate osteogenic cell migration in order to accelerate the osseointegration period [ 48 ].…”

Nano-Modified Titanium Implant Materials: A Way Toward Improved Antibacterial Properties

“…Zinc is one of the important trace elements in the human body and plays a vital role in the growth and development of bones ( Zhu et al, 2018 ). It was known that Zn can enhance the expression of M2 marker genes and proteins in macrophages.…”