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Human aging is becoming a common issue these days as it results in orthopaedic-related issues such as joints disorderness, bone-fracture. People with age = 60 years suffer more from these aforesaid issues. It is expected that these issues in human beings will ultimately reach 2.1 billion by 2050 worldwide. Furthermore, the increase in traffic accidents in young people throughout the world has significantly emerged the need for artificial implants. Their implantation can act as a substitute for fractured bones or disordered joints. Therefore, this study aims to focus on electron beam melted titanium (Ti)-based orthopaedic implants along with their recent trends in the field.

The main contents of this work include the basic theme and background of the metal-based additive manufacturing, different implant materials specifically Ti alloys and their classification based on crystallographic transus temperature (including α, metastable β, β and α + β phases), details of electron beam melting (EBM) concerning its process physics, various control variables and performance characteristics of EBMed Ti alloys in orthopaedic and orthodontic implants, applications of EBMed Ti alloys in various load-bearing implants, different challenges associated with the EBMed Ti-based implants along with their possible solutions. Recent trends and shortfalls have also been described at the end.

EBM is getting significant attention in medical implants because of its minor issues as compared to conventional fabrication practices such as Ti casting and possesses a significant research potential to fabricate various medical implants. The elastic modulus and strength of EBMed ß Ti-alloys such as 24Nb-4Zr-8Sn and Ti-33Nb-4Sn are superior compared to conventional Ti for orthopaedic implants. Beta Ti alloys processed by EBM have near bone elastic modulus (approximately 35–50 GPa) along with improved tribo-mechanical performance involving mechanical strength, wear and corrosion resistance, along with biocompatibility for implants.

Advances in EBM have opened the gateway Ti alloys in the biomedical field explicitly ß-alloys because of their unique biocompatibility, bioactivity along with improved tribo-mechanical performance. Less significant work is available on the EBM of Ti alloys in orthopaedic and orthodontic implants. This study is directed solely on the EBM of medical Ti alloys in medical sectors to explore their different aspects for future research opportunities.

The paper presents a wide range of post processing heat treatment cycles performed to Electron Beam Melted (EBM) Ti6Al4V alloy and establishes correlations of heat treat process to microstructure and mechanical property (microhardness). The research also identifies the optimal heat treatment to obtain the best microstructure and mechanical properties (hardness and tensile).

Rectangular bars fabricated using EBM was used to study the different heat treatment cycles. A variety of heat treatments from sub ß-transus, super ß-transus, near ß-transus and solution aircool plus ageing were designed. After the heat treatment process, the samples were analysed for, α lath width, prior ß grain size, microhardness and nanohardness. Tensile tests were done for the heat treated samples showing most refined α lath structure with uniform globular grains.

A clear correlation was observed between α lath width and the microhardness values. The solution aircooled plus aged samples exhibited the best refinement in α-ß morphology with uniform equiaxed grains. The tensile properties of the solution aircooled plus aged samples were comparable to that of the EBM printed samples and better than ASTMF1472 specifications.

There is hardly any prior work related to post processing heat treatment of EBM built Ti6Al4V other than HIP treatments. The variety of heat treatment cycles and its influence in microstructure and properties, studied in this research, gives a clear understanding on how to tailor final microstructures and select the optimal heat treatment process.

This paper aims to study both the mechanical properties and the corrosion behavior of the synthesized in situ (TiC-TiB₂) particulates/AZ91 magnesium matrix composite and compare the results with that of the conventional AZ91D alloy.

Scanning electron microscope (SEM) equipped with energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD) were used to study the surface morphology and crystalline structure. Mechanical compression tests were used to investigate the mechanical performance according to ASTM E9-89a. The corrosion behavior of the synthesized magnesium alloy was examined using both electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization techniques in dilute Harrison solutions.

The microstructure of the Mg composite showed a uniform distribution of reinforcing phases. Also, the reinforcing phases were formed without residual intermediate phases. The addition of titanium and boron carbides not only enhanced the mechanical properties of the matrix but also improve its corrosion behavior.

This is the first time that magnesium matrix composite has been to synthesized with TiC and TiB₂ particulates starting from starting from Ti and B carbides powder without adding aluminium using practical and low-cost technique (in situ reactive infiltration technique). This paper studies the corrosion behavior of synthesized Mg matrix in dilute Harrison solution and compares the results with that of conventional AZ91D.