4results about How to "High green strength" patented technology

The invention discloses a silicon nitride ceramic substrate and a preparation method thereof, and a preparation method of tape casting slurry, and the preparation method of the tape casting slurry comprises the following steps: step 1, slurry preparation: adding an organic solvent into pretreated silicon nitride powder, mixing, then adding a sintering aid, a binder, a flexibilizer and a dispersant, and carrying out ball milling in a ball mill for 12-24 hours to obtain slurry; uniform and stable slurry is prepared; and step 2, tape casting. By optimizing the preparation method of the silicon nitride tape-casting slurry, the stability and dispersity of the slurry are improved, so that the quality of a tape-casting film is ensured, and silicon nitride powder is uniformly dispersed in the slurry by adopting a specific sintering aid, an organic solvent, a binding agent and a dispersing agent and controlling parameters such as stirring speed and ball-milling time in the preparation process, so that the silicon nitride tape-casting slurry is prepared. Consistency and stability are high, the casting thickness is easy to control, the drying system is simple, and the green body strength and toughness are high.

The utility model discloses an aluminum oxide ceramic sealing test standard part green body dry pressing forming die which comprises a variable-diameter cylindrical positioning rod fixing die, a variable-diameter cylindrical positioning rod, a circular ring inner concave petal die, a cylindrical outer die, a circular ring gasket die, a circular ring column ejector rod and a die withdrawing groove. The variable-diameter cylindrical positioning rod fixing mold is used for fixing, supporting and positioning the variable-diameter cylindrical positioning rod; the variable-diameter cylindrical positioning rod has the functions of positioning, blank inner supporting and filler guide mold; the circular ring inner concave petal die consists of two petal dies and is positioned through a variable-diameter cylindrical positioning rod and a cylindrical outer die; the circular ring gasket die is positioned by a variable-diameter cylindrical positioning rod and a cylindrical outer die; the ceramic blank is filled between the circular ring inner concave petal die and the circular ring gasket die; the annular column ejector rod is positioned through the variable-diameter cylindrical positioning rod and the cylindrical outer mold; and demolding through the demolding groove. The forming die disclosed by the utility model can realize dry-pressing forming and convenient demolding of special-shaped ceramic green bodies, is simple and convenient to operate, and the obtained green bodies are high in strength and small in firing shrinkage.

This invention discloses a method for preparing yttrium-magnesium oxide (YMO) multiphase transparent ceramics using non-aqueous gel casting, belonging to the field of ceramic preparation technology. To overcome the problems associated with water-based gel casting, this invention provides a method for preparing YMO multiphase transparent ceramics using non-aqueous gel casting, comprising: ball milling Y2O3, MgO, a dispersant, and a non-aqueous solvent; then adding epoxy resin and a curing agent and ball milling again; the resulting ceramic slurry is defoamed, cured, and dried; then subjected to debinding, sintering densification, cooling, hot isostatic pressing, annealing, and polishing to obtain the YMO multiphase transparent ceramic. This invention overcomes the difficulties in preparing large-size Y2O3-MgO nano-multiphase infrared transparent ceramics and the problem of component inhomogeneity by designing a non-aqueous solvent system and selecting a suitable gel system, and can produce complex-shaped / large-size, uniformly composed YMO nano-multiphase ceramics.