偏硼酸盐为非氧化性熔剂,其分解试样能力之强和适应性之广是其它熔剂无法与之相比的。关于它的应用国内已有不少报导,但这些研究均采用高比例的硼砂(或硼酸)或偏硼酸锂。因此,其熔块很难被分解,生产中深感不便。本文依据苛性钠的低熔点(328℃)和共熔混合物熔点降低的原理以及偏硼酸盐分解试样的特点,确定以苛性钠-硼酸混合熔剂,对不同比例的熔剂作了对照试验。所用试剂均为分析纯。称取105℃烘干的蓝晶石试样1.0000克于石墨坩埚中,加入表1内不同比例的混合熔剂6克,加几滴 Borate is a non-oxidizing flux, its ability to break down the sample strong and adaptable other flux can not be compared with. There have been many reports about its application in China, but all of these studies use a high proportion of borax (or boric acid) or lithium metaborate. Therefore, the frit is difficult to be decomposed, so it is inconvenient to produce. Based on the principle of reducing the melting point of caustic soda (328 ℃) and melting point of eutectic mixture, and the characteristics of samples decomposed by metaborate, it was determined that caustic soda-boric acid mixed flux was used to control the flux of different proportions. The reagents used are of analytical grade. Weigh 105 ℃ dried kyanite sample 1.0000 g in a graphite crucible, add Table 1 different proportions of mixed flux 6 grams, add a few drops