用于六面顶压机的2种叶蜡石成分及传压性能对比

Comparison of compositions and pressure transmission performances of two kinds of pyrophyllites used in cubic press

分别对产自南非和中国的2种叶蜡石原矿和粉压块进行扫描电镜能谱(EDS)及X射线粉末衍射(XRD)分析,得出其主要化学成分和物相组成,并用Bi、Tl、Ba 3种物质的高压相变来原位标定合成腔体的压力。结果表明:南非叶蜡石原矿是伊利石型叶蜡石,国内叶蜡石原矿是水铝石型叶蜡石;900℃处理后的南非叶蜡石原矿中SiO2质量分数比国内叶蜡石的高约4.50%,且2种叶蜡石粉压块的压力发生效率基本相同。在Bi、Tl、Ba压力标定试验中,在10~50 MPa油压下用南非叶蜡石块为介质的压机右、前、上各缸前进位移比用国内叶蜡石块为介质的大约0.33 mm;在20~50 MPa油压下,试验前后的南非叶蜡石原矿及粉压块的密度较国内叶蜡石原矿及粉压块的低0.055~0.081 g/cm3。对南非叶蜡石粉压块制备方案进行优化,使其达到目前广泛使用的国内叶蜡石粉压块相同的密度,可替代国内叶蜡石粉压块使用。

Two kinds of pyrophyllites from South Africa and China were analyzed by scanning electron microscope energy dispersive spectroscopy(EDS)and X-ray powder diffraction(XRD).The main chemical compositions and phase compositions of pyrophyllite were obtained.The pressure of synthesis chamber was calibrated by high-pressure phase transformation of Bi,Tl and Ba.The results show that the South African pyrophyllite ore is illite-type pyrophyllite,and the Chinese pyrophyllite ore is diaspore-type pyrophyllite.The mass fraction of SiO2 in the South African pyrophyllite ore treated at 900℃is approximately 4.50%higher than that of the Chinese one,and the pressure generation efficiency of the two pyrophyllite powder briquettes is basically the same.In the pressure calibration test of Bi,Tl,Ba,the forward displacements of the right,the front and the upper cylinders of the press,the South African pyrophyllite as medium,under 10~50 MPa oil pressure are about 0.33 mm larger than those of the Chinese pyrophyllite.Before and after 20~50 MPa oil pressure test,the densities of the South Africa pyrophyllite raw ore and powder briquette are 0.055~0.081 g/cm3 lower than those of the Chinese pyrophyllite ore block and powder briquette.The preparation plan of the South African pyrophyllite powder briquette is optimized to make the density reach the same level as the currently widely used pyrophyllite powder briquette,which can replace its Chinese counterpart.