จำนวน Repository ( 2 )

พัฒนาโลหะมีค่าชนิดทังสเตนคาร์ไบต์ผ่านการรีไซเคิลหมุนเวียนมาใช้ใหม่เพื่อผลิตชิ้นส่วนโลหะความแข็งสูง
พัฒนาโลหะมีค่าชนิดทังสเตนคาร์ไบต์ผ่านการรีไซเคิลหมุนเวียนมาใช้ใหม่เพื่อผลิตชิ้นส่วนโลหะความแข็งสูง

This research was on the production of hardmetal from recovery of tungsten carbide tool scraps recycling through ball milling for 40 hours. The metal powder obtained which was of the size between 0.11-0.22 µm was composed of 96.69% of tungsten carbide (WC) 1.68% of tantalum (Ta) 1.21% of titanium (Ti) and 0.42% of niobium (Nb). When mixed with 5-15% cobalt binder metal cold isostatic press (CIP) sintered at 1450 ° C it became hardmetal work piece dimension 12.39 x 13.82 x 5.60 mm with 1410 HV hardness and 14.34 g/cm3 density. The result of S45C steel turning was tools life good. The research concluded that the hardmetal work piece produced by the developed material had suitable basic specification and would lead to the development in working in the future.

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Development of Process for Recovery Metal Carbide Powder from Cemented Tungsten Carbide Scraps
Development of Process for Recovery Metal Carbide Powder from Cemented Tungsten Carbide Scraps

The recycling of materials is the recovered process and the important approach for sustainable development. This research is to study recycling tungsten carbides from cemented carbide scraps by extracting the dissolved of binder phase and to study the un-dissolved substrate which stayed condition and size in WC particles. The experiment of this research starts in laboratory with electrolysis is found that the appropriate operating potential is 0.20-1.40 volts at 30-80 oc treated in 1N-7N HCl concentrations aqueous solution as well as the movement of solution and specimens had an effect on capacity of dissolution. Additionally these factors are affected to purity and passivation of WC particles. According to the above experiment it leads to design and create the semi-automatic cemented dissolution machine with electrolysis. This machine can contain the scraps up to 2.5 kilograms in rev 0-25 rpm (revolutions per minute) at electric current 0-50 ampere in electric voltage 0-15 volts. Its flowing process can be 15 lpm (litre per minute) and minute) and temperature is up to 90 oc. Furthermore there are the relative WC power invention processes included residues washing leaching ball milling drying screening and quality examination. The result of developed machine is capacity of tungsten carbide production is in the range 16-50 gram/hour the obtained powder is 97.49% of tungsten carbide (WC powder) which contained a few amount of cobalt. However the dissolution of cemented carbides with this machine can be selected the optimized factors to produce tungsten carbide (WC) to purify more than 99% ball milled them in the most suitable size and particle sized distribution between 0.30-20.00 μm. Afterwards combining cobalt 15% (WC-15%Co) and producing to cemented carbides insert tools rectangle as SNMG standard 120408 it appears that insert tools has a hardness not less than 1430 HV density not less than 14.10 g/cm³. In the other hands the production of tungsten carbides with advanced technology of dissolution machine and manufacturing machine to produce purely tungsten carbides powder has been required an investment charge of new research and development more than 9481888 baht.

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