Binder system is critical to the success of metal injection molding(MIM). A novel PEG based binder for MIM was developed, which was made of high density polyethylene (HDPE), polyethylene glycol (PEG), polymer W, stear...Binder system is critical to the success of metal injection molding(MIM). A novel PEG based binder for MIM was developed, which was made of high density polyethylene (HDPE), polyethylene glycol (PEG), polymer W, stearic acid(SA) and dioctyl phthalate (DOP). The components of binder have interactions with each other, so the binder have good compatibility. The thermal decomposition process of binder exhibits three stages during debinding. The binder could be debound by pyrolysis or solvent, and could easily be removed in a short time in ethanol without defects and evironmental concern. A lot of interconnected pores formed after solvent debinding, which is helpful to the escape of pyrolysis gases during subsequent thermal debinding or presintering. [展开更多
Pore opening and binder flow during the initial stage of thermal debinding in metal injection molded parts was investigated. Scaning electron microscopy(SEM) pictures of 316 L stainless steel parts using wax based bin...Pore opening and binder flow during the initial stage of thermal debinding in metal injection molded parts was investigated. Scaning electron microscopy(SEM) pictures of 316 L stainless steel parts using wax based binder show that small particles will move to the surface with the process of debinding. SEM pictures of different mass loss rate specimens indicate that initial pores will emerge when as little as 4% binder removes. During the initial stage of thermal debinding, vapor tension varies in different place due to the difference of curvature. Thus more binders will be removed in places with smaller cavity between metal powders, and in these places small openings emerge.展开更多
The thermal degradation behaviors of AlN green specimens were studied by thermogravimetry analysis during the ceramic powder injection molding debinding process. The optimum binder composition and the debinding cycle ...The thermal degradation behaviors of AlN green specimens were studied by thermogravimetry analysis during the ceramic powder injection molding debinding process. The optimum binder composition and the debinding cycle were demonstrated by observing the TGA and DTA plots of AlN green specimens and analyzing the microstructure at different temperatures. By adding HDPE into the PW EVA binder used in powder injection molding AlN can effectively reduce the mass lose rate in debinding process and improve the shape retention ability. At last, aluminum nitride ceramic with high room temperature thermal conductivity of 162.5?W·m -1 ·K -1 was produced. [展开更多
基金supported by the National Nature Science Foundation of China (NSFC) under grantNo. 50572049 the National High Technology Researchand Development Program of China ("863 Program") un-der grant No. 2007AA03Z522.
文摘Binder system is critical to the success of metal injection molding(MIM). A novel PEG based binder for MIM was developed, which was made of high density polyethylene (HDPE), polyethylene glycol (PEG), polymer W, stearic acid(SA) and dioctyl phthalate (DOP). The components of binder have interactions with each other, so the binder have good compatibility. The thermal decomposition process of binder exhibits three stages during debinding. The binder could be debound by pyrolysis or solvent, and could easily be removed in a short time in ethanol without defects and evironmental concern. A lot of interconnected pores formed after solvent debinding, which is helpful to the escape of pyrolysis gases during subsequent thermal debinding or presintering. [
文摘Pore opening and binder flow during the initial stage of thermal debinding in metal injection molded parts was investigated. Scaning electron microscopy(SEM) pictures of 316 L stainless steel parts using wax based binder show that small particles will move to the surface with the process of debinding. SEM pictures of different mass loss rate specimens indicate that initial pores will emerge when as little as 4% binder removes. During the initial stage of thermal debinding, vapor tension varies in different place due to the difference of curvature. Thus more binders will be removed in places with smaller cavity between metal powders, and in these places small openings emerge.
文摘The thermal degradation behaviors of AlN green specimens were studied by thermogravimetry analysis during the ceramic powder injection molding debinding process. The optimum binder composition and the debinding cycle were demonstrated by observing the TGA and DTA plots of AlN green specimens and analyzing the microstructure at different temperatures. By adding HDPE into the PW EVA binder used in powder injection molding AlN can effectively reduce the mass lose rate in debinding process and improve the shape retention ability. At last, aluminum nitride ceramic with high room temperature thermal conductivity of 162.5?W·m -1 ·K -1 was produced. [
