This study aims to investigate the effect of an aluminum chromium nitride (AlCrN) coating on tool wear and hole quality in the conventional drilling process of carbon fiber-reinforced plastic (CFRP) composites, titanium alloy (Ti), and CFRP–Ti stack workpieces popular in the aerospace industry. The advanced arc plasma acceleration (APA) method of physical vapor deposition (PVD) was used for all AlCrN coatings. The drilling experiments were conducted with uncoated drills as well as AlCrN-coated drills. When drilling CFRP only, the AlCrN coating was removed at the drill cutting edges and the margin area, which suggests the carbon fibers abraded the coatings. When drilling Ti only, the AlCrN-coated drill mitigated the Ti adhesion formation, which resulted in less tool wear. In addition, hole quality for both CFRP and Ti was improved when the coating was used versus the uncoated tool. The machinability of CFRP–Ti stacks in the drilling process was improved by utilizing the advanced AlCrN coating on the WC tool in terms of drilling forces and hole quality parameters such as average hole size, average hole roundness, hole surface roughness, and Ti exit burr height.
This study is conducted as a preliminary research to verify the feasibility of Ti-based Oxide dispersion strengthened (ODS) alloy. Pure-Ti powder is mixed with Y2O3 powder and subsequently, mechanically alloyed at -150oC. The Ti-based ODS powder is hot-isostatically pressed and subsequently hot-rolled for recrystallization. The microstructure consists of elongated grains and Y excess fine particles. The oxide particle size is larger than that of the typical Febased ODS steel. Tensile test shows that the tensile ductility is approximately 25%, while the strength is significantly higher than that of pure Ti. The high-temperature hardness of the Ti-ODS alloy is also significantly higher than that of pure Ti at all temperatures, while being lower than that of Ti-6Al-4V. The dimple structure is well developed, and no evidence of cleavage fracture surface is observed in the fracture surface of the tensile specimen.
One-dimensional rutile TiO2 is an important inorganic compound with applicability in sensors, solar cells, and Li-based batteries. However, conventional synthesis methods for TiO2 nanowires are complicated and entail risks of environmental contamination. In this work, we report the growth of TiO2 nanowires on a Ti alloy powder (Ti-6wt%Al- 4wt%V, Ti64) using simple thermal oxidation under a limited supply of O2. The optimum condition for TiO2 nanowire synthesis is studied for variables including temperature, time, and pressure. TiO2 nanowires of ~5 μm in length and 100 nm in thickness are richly synthesized under the optimum condition with single-crystalline rutile phases. The formation of TiO2 nanowires is greatly influenced by synthesis temperature and pressure. The synthesized TiO2 nanowires are characterized using field-emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), and high-resolution transmission electron microscopy (HR-TEM).
The purpose of this study is to decrease a stress shielding effect shown in the hip joint. To conduct this study, the clad materials were produced by using an explosion welding method with two materials that were different in the elastic modulus like Ti-6Al-4V alloy and pure Ti. As for the clad materials, the Ti-6Al-4V alloy with large elastic modulus was designed as the neck of femur, and the pure Ti with small elastic modulus as the body of femur. The joints of clad materials formed by the explosion welding showed the typical wave shape, and its thickness was about 0.2㎛. New crystal or grain structure was not formed in the joints. In addition, the Vickers hardness in the joints formed the middle value between the base metal and clad metal. As a result of manufacturing prototype by processing the clad materials in three dimensions, this study gained good shape, and if it is to be applied to clinical in the future, this researcher can expect good results. From the result of this research above, it may be summed up as follows. It is considered as the stress shielding phenomenon showed on the hip joint can be decreased to a certain degree if this researcher is to utilize two clad materials with different elastic modulus like Ti-6Al-4V alloy and pure Ti
In this study, a large modulus of elasticity of the titanium alloy in use, to create artificial hip stress shielding effect appears to reduce the head portion is excellent in the strength of Ti-6Al-4V, making bone pusher which requires low elastic modulus relative modulus of pure titanium grade 2, using a small two metal after welding by explosion welding hip was made. Explosion pressure welding by the welding region with respect to the mechanical properties and the tissue was observed.
Titanium alloys and Titanium alloy-based particulate composites were synthesized using the blended elemental P/M route. First, processing conditions such as the fabrication of master alloy powder were investigated. Ti-6Al-4V, Ti-5Al-2.5Fe, Ti-6Al-2Sn-4Zr-2Mo, IMI685, IMI829, Timetal 1100 and Timetal 62S, and Ti-6Al-2Sn-4Zr-2Mo/ 10%TiB and Timetal 62S/10%TiB were then synthesized using the optimal processing conditions obtained. The microstructures and mechanical properties such as tensile strength and high cycle fatigue strength were evaluated.
Mechanical properties of metal injection molded titanium and titanium alloy parts were investigated in this study. Material powders with low oxygen content and spherical shape were obtained by electrode induction-melting gas atomization which could melt and atomize titanium and titanium alloy bars with no touch on crucible or tundish. Tensile specimens were fabricated from obtained powders by metal injection molding process. Tensile strength of the specimens increases with increasing oxygen content. This result corresponds to a tendency of wrought metal.