经过五年多的研发，我公司已能批量生产微钠白刚玉块、段砂、粒度号砂、磨粉、微钠白刚玉微粉等。

After 5 years of research and development, Zhengzhou Yufa Abrasive Co.Ltd has already mastered the technology of producing low-sodium white corundum block,  section corundum sand, grain corundum sand, grinding powders, and low-sodium oxide white corundum micropowders in quantity.

微钠白刚玉微粉是由我公司生产的微钠白刚玉块经深度精加工而成。

Low-sodium white corundum micropowder are carefully manufactured from the low-sodium white corundum blocks made by ourselves.

微钠白刚玉是指：含氧化钠量在0.01－0.09％之间的白刚玉。它的原料是经过深加工的氧化铝。微钠白刚玉是白刚玉中一种含氧化钠量较低的产品。普通白刚玉中的氧化钠含量在0.2—0.6％之间。

Low-sodium white corundum indicates the white corundum in which the content of sodium oxide is between 0.01-0.09%, and the raw material of which is   alumina processed in depth . Low-sodium white corundum is a type of low sodium-content product. By contrast, the sodium content in the common white corundum is between 0.2%—0.6％ .

微钠白刚玉的主相是α-Al2O3。

The main phase of the low-sodium white corundum is α-Al2O3.

氧化钠对于白刚玉是一种有害杂质，它与氧化铝在熔融状态下生成β-Al2O3，生成量随氧化钠含量的增加而增大。β-Al2O3的熔点低，体密低，硬度低。白刚玉中的Na2O主要以Na2O·11AL2O3(β-Al2O3)的形式出现，如果氧化铝原料中含有0.6%以上的氧化钠，利用它生产的白刚玉中就会含百分之十以上的β-Al2O3

Sodium oxide is a harmful impurity in white corundum. It can react chemically with alumina in melting state and generate β-Al2O3 . The higher the sodium oxide content is, the more the β-Al2O3 forms. β-Al2O3 is featured with low melting point, low bulk density, and low hardness. The sodium oxide is coming in the form of Na2O·11AL2O3(β-Al2O3). If the sodium oxide content in alumina is higher than 0.6%, the β-Al2O3 content in the produced white corundum will be higher than 10% .

β-Al2O3和α-Al2O3相比有‘三低’，一是熔点低，二是密度低，三是硬度低,具体如下表所示。                                                              

Compared to α-Al2O3,β-Al2O3 has lower melting point, lower density, and lower hardness, as shown in the following table.

我公司生产的微钠白刚玉α相率可达98％以上。

The α-Al2O3 content of the low-sodium oxide white corundum produced by Yufa is higher than 98%.

下表所示是我公司为某单位生产的微钠白刚玉1-0段砂的化学成份

The following table shows the chemical compositions of the low-sodium oxide white corundum 1-0 section sand for a customer.