A Short Review on Cellular Structure Design and Selective Laser Melting using Bio-compatible Ti6Al4V Material

transport and cell can be well-designed A Short and Laser Additive Manufacturing (AM) is one of the most significant in bio medical application to manufacture the implant for bone repairing applications. The implant has a cellular structure inside which is used in biomedical implant, that is used to allow our bone ingrowth. The implant material should be biodegradable, non-toxic, have similar biomechanical properties and have a porous. Due to this reason it is very significant important to design and produce implant with high accuracy. In this review, design cellular structure and AM technology of fabrication biomedical implant using Selective Laser Melting (SLM) process is detail reviewed. As per According to necessities of medical orthopedic applications, the choice of high quality AM technology printing technique and Ti6Al4V metal powder were surveyed. Aside from this biomedical -AM printing application, the biocompatible Ti6Al4V alloy will be broadly used in implant bone application, in addition to that used for scaffold in tissue engineering. Abbreviations: EBM:


Introduction
In biomedical engineering, the medical orthopedic is a speedily developing multidisciplinary research area to rebuild implants and scaffolds [1] by using a biocompatible and biodegradable implant and scaffolding structure. As described early, it is very important to manufacture implants with high accuracy and precision. The implant has been manufactured using various AM methods such as SLM, Electron Beam Melting (EBM), In these methods, the smallest printable size is 50-200μm which is too small to be used for some biomedical scaffold or certain producing big in size on biomedical implant application [2].

Design of Cellular Structures
In biomedical orthopedics application, lattice structures are used as cellular implant that attempt to function of bone and mimic the structure [3]. The cellular structures can be used either asan implant or scaffold. In either case, the cellular implant ought to be designed to such an extent that its mechanical performance similar that of human bone, though considering different issues that optimized bone ingrowth. For instance, the mass transport and cell migration in our bone tissue can be controlled through well-designed ofpermeabilitycellular structure structures [4,5].
Additive Manufacturing (AM) is one of the most significant in bio medical application to manufacture the implant for bone repairing applications. The implant has a cellular structure inside which is used in biomedical implant, that is used to allow our bone ingrowth. The implant material should be biodegradable, non-toxic, have similar biomechanical properties and have a porous. Due to this reason it is very significant important to design and produce implant with high accuracy. In this review, design cellular structure and AM technology of fabrication biomedical implant using Selective Laser Melting (SLM) process is detail reviewed. As per According to necessities of medical orthopedic applications, the choice of high quality AM technology printing technique and Ti6Al4V metal powder were surveyed. Aside from this biomedical -AM printing application, the biocompatible Ti6Al4V alloy will be broadly used in implant bone application, in addition to that used for scaffold in tissue engineering. During the most recent two decades, a number ofesearchershave been investigated for designing cellular implant for scaffold which considered the properties of cellular implant such as biocompatibility, mechanical properties, bio-functionality and biodegradability of the cellular implant of scaffold [6][7][8][9].In this review, we focused on the design tools for cellular structure aimed   Tessellation method [8,9].

SLM Fabrication of Cellular Structures
Based on ASTM definition of AM is "technique of joining materials to make parts by the fashion layer upon layer from STL format rather than subtractive fabrication process.

Bio-Compatible Ti6Al4V
Ti6Al4V alloys are extensively used as biomedical implant due to its many beneficial assets, such as, low stiffness, high specific strength-to-weight ratio, satisfactory biocompatibility, superior corrosion resistance, good fatigue resistance, and so on [10]. So, Ti6Al4V have been commonly used in biomedical application, such as oral repair, artificial joints, scaffold and hip implant [11][12][13]

Conclusion
In spite of the fact that few AM technologies are used for biomedical applications, SLM process can print cellular implant biodegradable / biocompatible implant with higher resolution and high accuracy dimension. The mechanical and biological properties are the main concern while Ti6Al4V cellular implant fabricating using SLM process.Presently, cellular metallic implant manufactured by SLM, according to in vitro biological evaluation, are not achieved very clear conclusion, this is because of design cellular implant have a lot variable such as pore shape, pore size, porosity, interconnectivity and so on. This means that any change in one variables can affect the performance of the implant. Therefore, the benefit of using permeability as variable design could the combination of the effect of the aforementioned parameters (pore size, porosity etc.) this revealed that the higher permeability implant was suitable for bone growth.