Ni-based alloys are a special class of engineering material with excellent corrosion resistance in harsh environments. However, microstructural changes due to the solidification, may result in solidification cracks and reduction in the corrosion resistance. Knowing the microchemical and microstructural evolutions during the solidification of these alloys is essential for the understanding of the relationship between the metallurgical aspects and the properties. This research presents a new insight on the solidification path of alloy 625 weld metals deposited by the TIG cold wire process on the C–Mn steel plates. After the welding, samples having been extracted and evaluated by the scanning electron microscope, transmission electron microscopy and energy dispersive X-ray spectroscopy techniques. The results showed the presence of two types of secondary phases, identified as Laves phase and complex nitride/carbide particles. Due to the presence of nitrides particles, stable in the solid state during the melting of the alloy, during the solidification it is noted the occurrence of a complex nitride/carbide precipitation. This implies in a new route to explain the solidification of the aforementioned alloy

Titanium and its alloys, especially Ti-6Al-4V, are widely studied in implantology for their favorable characteristics. However, challenges remain, such as the high modulus of elasticity and concerns about cytotoxicity. To resolve these issues, research focuses on β-type titanium alloys that incorporate elements such as Mo, Nb, Sn, and Ta to improve corrosion resistance and obtain a lower modulus of elasticity compatible with bone. This review comprehensively examines current β titanium alloys, evaluating their mechanical properties, in particular the modulus of elasticity, and corrosion resistance. To this end, a systematic literature search was carried out, where 81 articles were found to evaluate these outcomes. In addition, this review also covers the formation of the alloy, processing methods such as arc melting, and its physical, mechanical, electrochemical, tribological, and biological characteristics. Because β-Ti alloys have a modulus of elasticity closer to that of human bone compared to other metal alloys, they help reduce stress shielding. This is important because the alloy allows for a more even distribution of forces by having a modulus of elasticity more similar to that of bone. In addition, these alloys show good corrosion resistance due to the formation of a noble titanium oxide layer, facilitated by the incorporation of β stabilizers. These alloys also show significant improvements in mechanical strength and hardness. Finally, they also have lower cytotoxicity and bacterial adhesion, depending on the β stabilizer used. However, there are persistent challenges that require detailed research in critical areas, such as optimizing the composition of the alloy to achieve optimal properties in different clinical applications. In addition, it is crucial to study the long-term effects of implants on the human body and to advance the development of cutting-edge manufacturing techniques to guarantee the quality and biocompatibility of implants.