The tungsten carbide powder which recycled from the scarps of cemented tungsten carbide produces the purity of 99%. Using this tungsten carbide powder to manufacture a cutting tool and test its properties are the main objective of this work. Based on the standard SNMG 120408 the cutting tool with the dimension of 12.7x12.7x4.76 is fabricated. With the 100 hours of Ball milling grinding Cobalt mixing and sintering at 1430 °C the experimental result is impressive. At 15% of mixedcobalt the cutting tool with the hardness of 2031.6 HV be able to cut S45C steel in the feed rate of 0.2 meters per revolution and 45 m/min in the cutting speed. Besides that it provides the depth of cut of 0.25 mm and when it reaches the cutting distance of 4200 mm the surface roughness is 3.65 μm. In comparison with the cutting tool made of imported tungsten carbide powder which has a hardness of 1254 HV it turned out that our cutting tool has the equivalent quality in terms of hardness and wear resistance. Hence this work is considered to be a material development and a tungsten carbide cutting tool manufacture those would be the vital base to lead us to a commercial production.

This study is meant to help develops better facilities for Tungsten Carbide powder production process. The 10 kg-capacity machine used was able to produce 85 -95.49 percent purity Tungsten carbide powder. When measured most of the particle sizes and distribution between 0.03-350.00 !lm. which are considered large sized. More than that those tungsten carbide particles are contaminated by other kinds of metal especially Cobalt binder. We have tried to improve the Tungsten Carbide manufacturing processes by combining more steps including ball milling drying and screening. After 24-hours ball milling process the result showed that we were able to produce smaller Tungsten Carbide paliicles sizing from 0.025 to 30.00 ~lm. The obtained particles are also rounder and with 99.50 percent purity. They are also easier to grade. The Tungsten Carbide manufacturing technology yet needs a further development to eventually produce the desired hard material.

This research article aims to study of the atomizer nozzle pattern in the gas atomization process. The production of metal powder by using a gas atomization process. It is the most popular process. This process is used in various industry and engineering application. However there is lack of information on the production of various precious metal powders in the jewelry manufacturing industry both in the country and abroad. For this reasons the research team is interested in applying this process for the Thai jewelry manufacturing industry. Currently the jewelry industry is in a transitional period of manufacturing technology with an increased focus on powder metallurgy technology. The production of metal powder by using a gas atomization process consisting of the following 3 steps: melting making of atomized molten metal cooling and solidifying for solid particles under a controlled gas atmosphere. Factors affecting particle shape particle size and particle size distribution are consisting of inert gas type molten metal temperature and the configuration or pattern of the nozzle that are different characteristics. The results can be concluded that Close-Coupled Nozzle is the most suitable nozzle for production due to the highest productivity providing the smallest particle size and spherical granular shape. The information from this study will be useful for the Thai jewelry manufacturing industry.