The role of cold nitrogen gas and oil mist on tool wear and surface roughness is investigated in turning the K424 nickel-base super alloy with Sialon and SiC whisker-reinforced alumina ceramic tools. A new cooling sys...The role of cold nitrogen gas and oil mist on tool wear and surface roughness is investigated in turning the K424 nickel-base super alloy with Sialon and SiC whisker-reinforced alumina ceramic tools. A new cooling system is developed and used to lower the temperature of the compressed nitrogen gas. Experiments are performed in three different cooling/lubrication modes, i.e. the dry cutting, the cold nitrogen gas （CNG）, and the cold nitrogen gas and oil mist （CNGOM）. Experimental results show that the depth-of-cut notching severely limits the tool life in all the cooling/lubrication modes. Compared with the dry cutting, the use of CNG and CNGOMcan yield higher wear rate of depth-of-cut notching and worse surface finish.展开更多
When machining D60 steel by high speed turn-milling under the different cooling and lubricating conditions, the cutting performance and the wear mechanism of the cermet cutter are researched. With water soluble coolin...When machining D60 steel by high speed turn-milling under the different cooling and lubricating conditions, the cutting performance and the wear mechanism of the cermet cutter are researched. With water soluble cooling fluid, the wear performance of the cermet cutter is bad, and does not adapt to the requirements of machining. However, when machining D60 by high speed turn-milling is under dry conditions, the wearing performance of the cermet cutter is very good and the cutting time lasts almost 3 hours. The wear mechanism of the cermet cutter under the water soluble cooling fluid is different from the dry condition. With the water soluble cooling fluid, a great deal of little chap units are formed since high frequency alternates heat stress. The crash and desquamate of these chap units is the main cause of the cutter wearing. Under dry cutting conditions, it is the main cause of cermet cutter wear in the felting phase intenerating causing rigid phase grains to fall.展开更多
X2CrNiMoN25-7-3 duplex stainless steel is suitable for chloride-containing environments such as seawater because it has excellent pitting corrosion resistance. Duplex stainless cast steel is often used to accommodate ...X2CrNiMoN25-7-3 duplex stainless steel is suitable for chloride-containing environments such as seawater because it has excellent pitting corrosion resistance. Duplex stainless cast steel is often used to accommodate the complexity of part geometry at joints. However, machining after casting is indispensable. This study evaluated the cutting characteristics of stainless cast steel. Adhesion of the cutting edge was weak at high cutting speeds, but tool wear was large. Diffusion and reactions between the work-pieces and the tool edge were investigated. Slight inter-diffusion and a reaction phase were observed, but the bond-ability was low.展开更多
The objective of this research is to reduce waste in the production ceramics of Ceramics Factory in Thailand. The 7 Quality Control Tools （7 QC Tools） were implemented including Check sheet, Graph, Pareto diagram an...The objective of this research is to reduce waste in the production ceramics of Ceramics Factory in Thailand. The 7 Quality Control Tools （7 QC Tools） were implemented including Check sheet, Graph, Pareto diagram and Fishbone diagram, which were used to analyze and solve the problems. It was found that most of the wastes come from burning ceramics process. The kilns and trolleys has been used for a long time. Furthermore, the equipment and parts were damaged from lack of maintenance. The non-standard of product arrangement method into the kilns were the cause of waste. Thus, the researcher improved trolleys into the kilns and designed a fixture to help worker to product arrangement. The results of the research gathered data from quality inspection department. Then comparing data before the improvement （between September 2013 to December 2013） and after the improvement （between November 2014 to February 2015）, the wastes are reduced from 8.97% to 0.29%. The result of improving is very efficiency because it can reduce the wastes by 8.68%.展开更多
文摘The role of cold nitrogen gas and oil mist on tool wear and surface roughness is investigated in turning the K424 nickel-base super alloy with Sialon and SiC whisker-reinforced alumina ceramic tools. A new cooling system is developed and used to lower the temperature of the compressed nitrogen gas. Experiments are performed in three different cooling/lubrication modes, i.e. the dry cutting, the cold nitrogen gas （CNG）, and the cold nitrogen gas and oil mist （CNGOM）. Experimental results show that the depth-of-cut notching severely limits the tool life in all the cooling/lubrication modes. Compared with the dry cutting, the use of CNG and CNGOMcan yield higher wear rate of depth-of-cut notching and worse surface finish.
文摘When machining D60 steel by high speed turn-milling under the different cooling and lubricating conditions, the cutting performance and the wear mechanism of the cermet cutter are researched. With water soluble cooling fluid, the wear performance of the cermet cutter is bad, and does not adapt to the requirements of machining. However, when machining D60 by high speed turn-milling is under dry conditions, the wearing performance of the cermet cutter is very good and the cutting time lasts almost 3 hours. The wear mechanism of the cermet cutter under the water soluble cooling fluid is different from the dry condition. With the water soluble cooling fluid, a great deal of little chap units are formed since high frequency alternates heat stress. The crash and desquamate of these chap units is the main cause of the cutter wearing. Under dry cutting conditions, it is the main cause of cermet cutter wear in the felting phase intenerating causing rigid phase grains to fall.
文摘X2CrNiMoN25-7-3 duplex stainless steel is suitable for chloride-containing environments such as seawater because it has excellent pitting corrosion resistance. Duplex stainless cast steel is often used to accommodate the complexity of part geometry at joints. However, machining after casting is indispensable. This study evaluated the cutting characteristics of stainless cast steel. Adhesion of the cutting edge was weak at high cutting speeds, but tool wear was large. Diffusion and reactions between the work-pieces and the tool edge were investigated. Slight inter-diffusion and a reaction phase were observed, but the bond-ability was low.
文摘The objective of this research is to reduce waste in the production ceramics of Ceramics Factory in Thailand. The 7 Quality Control Tools （7 QC Tools） were implemented including Check sheet, Graph, Pareto diagram and Fishbone diagram, which were used to analyze and solve the problems. It was found that most of the wastes come from burning ceramics process. The kilns and trolleys has been used for a long time. Furthermore, the equipment and parts were damaged from lack of maintenance. The non-standard of product arrangement method into the kilns were the cause of waste. Thus, the researcher improved trolleys into the kilns and designed a fixture to help worker to product arrangement. The results of the research gathered data from quality inspection department. Then comparing data before the improvement （between September 2013 to December 2013） and after the improvement （between November 2014 to February 2015）, the wastes are reduced from 8.97% to 0.29%. The result of improving is very efficiency because it can reduce the wastes by 8.68%.
