The solvent debinding of water soluble binder in powder injection moulding (MIM) was investigated systematically, including the effects of solvent types, temperature and the thickness of green parts on the solvent deb...The solvent debinding of water soluble binder in powder injection moulding (MIM) was investigated systematically, including the effects of solvent types, temperature and the thickness of green parts on the solvent debinding rate. After studying the debinding of a green part with a thickness of 4.26 mm, it was found that, the debinding rate of polyethylene glycol(PEG) in water and alcohol was high initially, and then decreased; however, it would increase with temperature increasing. At room temperature, the dissolution rate of PEG in water was higher than that in alcohol, but the latter would be much faster with temperature increasing because the debinding activation energy in alcohol was 51.44 kJ·mol -1 ·K -1 , much higher than 24.23 kJ·mol -1 ·K -1 in water. With a green part thickness larger than 4.26 mm, the debinding was controlled by diffusion; but with that smaller than 2.36 mm, the debinding was controlled by both dissolution and diffusion.展开更多
A new wax oil polyethylene binder was developed for Fe 2Ni powder injection molding. The advantages of both wax based and oil based binders were acquired. Moreover, the debinding solvent could be recycled. The miscibi...A new wax oil polyethylene binder was developed for Fe 2Ni powder injection molding. The advantages of both wax based and oil based binders were acquired. Moreover, the debinding solvent could be recycled. The miscibility of the binder ingredients and the characteristics were evaluated. The results show that the maximum powder loading can reach 60%(volume fraction), and the two direction debinding rate is over 2 mm/h. The drying time for 6.37 mm thick samples is less than 20 min. The recycle ratio of the debinding solvent is over 95%.展开更多
文摘The solvent debinding of water soluble binder in powder injection moulding (MIM) was investigated systematically, including the effects of solvent types, temperature and the thickness of green parts on the solvent debinding rate. After studying the debinding of a green part with a thickness of 4.26 mm, it was found that, the debinding rate of polyethylene glycol(PEG) in water and alcohol was high initially, and then decreased; however, it would increase with temperature increasing. At room temperature, the dissolution rate of PEG in water was higher than that in alcohol, but the latter would be much faster with temperature increasing because the debinding activation energy in alcohol was 51.44 kJ·mol -1 ·K -1 , much higher than 24.23 kJ·mol -1 ·K -1 in water. With a green part thickness larger than 4.26 mm, the debinding was controlled by diffusion; but with that smaller than 2.36 mm, the debinding was controlled by both dissolution and diffusion.
文摘A new wax oil polyethylene binder was developed for Fe 2Ni powder injection molding. The advantages of both wax based and oil based binders were acquired. Moreover, the debinding solvent could be recycled. The miscibility of the binder ingredients and the characteristics were evaluated. The results show that the maximum powder loading can reach 60%(volume fraction), and the two direction debinding rate is over 2 mm/h. The drying time for 6.37 mm thick samples is less than 20 min. The recycle ratio of the debinding solvent is over 95%.
