Recently, lightweight materials centered on the future mobility industry are used in various parts such as battery housings and EV platform frames to improve fuel efficiency of automobile engines. Polycrystalline Diamond (PCD) tools are in demand by parts processing companies to improve productivity for machining lightweight parts. PCD drills have excellent cutting performance and wear resistance in high-speed machining. They are expected to grow in the global cutting tool market in the future. Research is needed to improve their performance. In this study, PCD gun drill and twist drill were respectively manufactured using brazing technology. Comparative machining experiments were then conducted. The PCD gun drill is a straight-shaped tool with a PCD tip brazed to a tool body groove for the tip to enter the cutting edge. The PCD twist drill is a spiral-shaped tool with a PCD drill blank brazed to a V-shaped butt joint with the tool body and an internal groove. Both PCD drills were successfully manufactured and evaluated for dimensional accuracy and surface quality by machining aluminum alloy materials with MCT equipment. In the future, we will evaluate not only aluminum materials, but also various machining materials.

In recent years, the demand for lightweight parts has been gradually increasing, particularly in the E-mobility industry. Among lightweight materials, aluminum alloys are highly beneficial for improving the fuel efficiency of automobile engines due to their lighter weight compared to iron-based materials. As electric vehicles become more prevalent, aluminum alloys are also extensively used in components such as battery housings and EV platform frames. To enhance productivity, aluminum parts processing companies require Polycrystalline Diamond (PCD) cutting tools for high-speed and ultraprecision processing. PCD cutting tools are known for their excellent cutting performance and wear resistance in highspeed aluminum machining, and they are anticipated to have significant growth potential in the global cutting tool market. In this study, we manufactured three types of PCD cutting tools (Drill, Endmill, and Reamer) using a self-developed brazing device and analyzed the machining surface quality through experiments. The results showed that the brazing joint quality of the PCD cutting tools was high, and the differences in surface roughness values under various machining conditions were minimal, confirming no issues with machining performance. Future research will focus on evaluating machining precision and tool life through comparative experiments with advanced PCD cutting tools from overseas.

Drill processing is essential in various industries, such as automobiles and aviation. Carbide is mainly used for drilling, but cermet is also one of the most used materials. Since cermet has low reactivity with iron and low reactivity at high temperatures, excellent surface roughness can be obtained. However, experimental research comparing the performance of carbide and cermet drills is lacking. The purpose of this study was to investigate the difference in the cutting characteristics of cermet and carbide tools. The experimental conditions were feed rates of 150, 200, 250, and 300 ㎜/min and 1,000, 1,500, and 2,000 revolutions per minute. S45C was used as the workpieces. In this study, surface roughness, inner diameter, and spindle load were derived as experimental results and used as indicators to evaluate the performance of carbide and cermet drills. The results showed that the performance of the cermet drill was superior to that of the carbide drill.

Scaffolds for bone tissue engineering (BTE) should accomplish appropriate mechanical, cell interaction, and new bone ingrowth properties. Among calcium phosphate (CaP) based bio-ceramics used for preparing scaffolds, biphasic calcium phosphate (BCP) is attracting great interest for fabricating BTE scaffolds owing to its excellent biocompatibility and osteoconductivity. Fused deposition modeling (FDM) is an additive manufacturing technology commonly used for modeling, prototyping, and production applications. It is one of techniques used for 3D printing. The main purpose of this study was to develop new fabrication process of BCP scaffolds based on extrusion moulding using a 3D printer. Through the 3D printer, we showed new fabrication process for making scaffold mould and extrusion device parts that could be combined with tension-compression test machine. Line width, pore size, and porosity of these fabricated BCP scaffolds were measured and calculated. Mechanical properties and cell proliferation results of these BCP scaffolds were then evaluated.

Recently, research on bone fracture and osteoplasty using ultrasonic bone surgery unit has been ongoing in the fields of dentistry, plastic surgery, and otorhinolaryngology. However, detailed data evaluation with ultrasonic bone surgery unit has not been conducted to date. In this study, we developed handpiece moving system (HMS) for cutting performance evaluation. In the experimental setup of HMS, a handpiece was immobilized, and bone samples from cortical bone of bovine leg were prepared. Also, the experimental process was described in detail, and a basic experiment was carried out to evaluate the cutting performance. Future study is required on all experimental process conditions by HMS.