The charge for growing single crystals of corundum purple mix


C30B11/10 - Solid or liquid components, e.g. Verneuil method

 

(57) Abstract:

The invention relates to the growing of single crystals of corundum blue-violet range of colors and can be used in the jewelry industry. Charge on the basis of aluminum oxide contains coloring additives titanium, iron, chromium, cobalt, vanadium, Nickel and copper, as well as mineralizers additives manganese, calcium, zinc and magnesium in the following ratio, wt. based on aluminum oxide: titanium 0,030 0,0070; iron 0,0001 0,7000; chrome 0,0001 - 0,7000; cobalt 0,0001 0,7000; vanadium 0,0001 0,7000; Nickel 0,0001 0,7000; copper 0,0001 0,7000; manganese 0,0001 0,0500; calcium 0,0001 0,0030; magnesium 0,0001 0,0040; zinc 0,0001 - 0,0030; alumina rest. Crystals grown by the Verneuil method, and then annealed in vacuum. table 1.

The invention relates to the composition of the charge for synthetic single crystals of corundum blue-purple range of colours are available for use in the jewelry and watch industry, but also in other areas where required colored crystals of corundum.

Known mixture for growing single crystals of corundum gamma blue paint containing impurities of titanium and iron [1]

The closest in technical essence to the invention awseome additives titanium, iron and chromium [2]

The aim of the invention is the creation of charge for growing single crystals of corundum, with shades in a wide range of blue-violet range of colors.

This is achieved by introducing into the mixture an additional coloring impurities cobalt, vanadium, Nickel and copper and as mineralizers additives manganese, calcium, zinc and magnesium in the following ratio of components (wt. based on aluminium oxide):

Titanium 0,0300-0,0070

Iron 0,0001-0,7000

Chrome 0,0001-0,7000

Cobalt 0,0001-0,7000

Vanadium 0,0001-0,7000

Nickel 0,0001-0,7000

Copper 0,0001-0,7000

Manganese 0,0001-0,0500

Calcium 0,0001-0,0030

Magnesium 0,0001-0,0040

Zinc 0,0001-0,0030

Alumina Rest.

To improve the quality of the charge of coloring impurities are introduced in the form of a solution of salts containing the same anion with a basic substance that provides more uniform dispersion powder composition.

P R I m m e R. In alumo-ammonium alum "OFS", "z h", "analytical grade" or "h" is entered coloring impurities in the form of solutions of sulfate salts in quantities specified in the table in terms of elements. After stirring the mixture is put in a quartz bowl and fired in a chamber furnace for 1.5-2 h at 112 From the resulting powder by the method of Verneuil crystals were grown.

Intervals coloring admixtures were selected due to the large number of experiments. The lower limit is due to the fact that the further reduction of impurities leads to the production of almost colorless crystals, and the upper limit is due to the fact that further increase in the content of impurities leads to cracking of the crystals and reduce the yield of crystals.

Temperature range of the firing of the charge 1120-1150aboutTo ensure complete decomposition of the starting compounds and the formation of aluminum oxide with coloring impurities. At temperatures below 1120aboutWith powder of aluminum oxide contains a significant amount of anion SO32-(tenths of percent), which leads to the formation of single crystals of the bubbles. At temperatures above 1150aboutWith deteriorating dispersion powder composition of aluminum oxide, which leads to the formation of neprapuwju.

After growing crystals may be subjected to vacuum annealing in order to intensify the color, produce new kinds of painting, removing pokerstove stress. For stress relieving the crystals are subjected to heat treatment in vacuum at 510 mm RT.article within 24 h at 190020

The invention allows substantially the Aly, sapphire, kunzite, amethyst, etc.

The CHARGE FOR GROWING single CRYSTALS of CORUNDUM PURPLE MIX color method Verneuil, containing aluminum oxide and coloring additives titanium, iron and chromium, wherein the mixture additionally contains a dye in the blue-violet range of additives of cobalt, vanadium, Nickel and copper, and as mineralizers additives manganese, calcium, zinc and magnesium in the following ratio of components, wt. based on aluminum oxide:

Titanium 0,03 0,007

Iron 0,0001 0,7

Chrome 0,0001 0,7

Cobalt 0,0001 0,7

Vanadium 0,0001 0,7

Nickel 0,0001 0,7

Copper 0,0001 0,7

Manganese is 0.0001 to 0.05

Calcium is 0.0001 0.003

Magnesium 0,0001 0,0040

Zinc is 0.0001 0.003

Alumina Rest

 

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