十二烷基苯磺酸钠对陶瓷结合剂及金刚石分散性的影响

Effect of sodium dodecyl benzene sulfonate on vitrified bond and dispersion of diamond

采用溶胶–凝胶法制备陶瓷结合剂粉末和陶瓷结合剂/金刚石混合粉末以及相应的块体材料。研究分散剂(十二烷基苯磺酸钠)质量分数为0~4.02%时,其对陶瓷结合剂物相、耐火度、弯曲强度和热膨胀系数等的影响,以及其对M2.5/5金刚石在陶瓷结合剂/金刚石混合粉末中分散性的影响。结果表明:分散剂质量分数为1.34%时,陶瓷结合剂的耐火度、弯曲强度和热膨胀系数与未添加分散剂时相比未发生明显变化,其中耐火度为700℃、弯曲强度为45 MPa、热膨胀系数为4.3×10^(-6)℃^(-1);当分散剂的质量分数从1.34%增加至4.02%时,陶瓷结合剂的耐火度降至600℃,弯曲强度降至28 MPa,热膨胀系数增至7.5×10^(-6)℃^(-1);分散剂质量分数为1.34%时,M2.5/5金刚石均匀分散在陶瓷结合剂/金刚石复合材料中,且未引起复合材料的性能变化。

Vitrified bonds and the mixed powders of diamond and vitrified bonds are prepared by sol-gel and corres-ponding bulk composites are fabricated.The effect of mass fraction of dispersant(sodium dodecyl benzene sulfonate)ranged from 0 to 4.02%on property of vitrified bond is studied,including composition phase of vitrified bond,refractor-iness,bending strength and thermal expansion coefficient.The dispersibility of M2.5/5 diamond dispersed in the mixed powders is investigated.The result reveals that when the mass fraction of dispersant was 1.34%,refractoriness of 700℃,bending strength of 45 MPa and coefficient of thermal expansion of 4.3×10^(-6)℃^(-1)have no change compared with that without addition of dispersant.Besides,with the dispersant increasing from 1.34%to 4.02%the refractoriness of vitrified bond prepared by sol-gel technique decreases to 600℃and bending strength decreases to 28 MPa.The thermal expansion coefficient of vitrified bond increases to 7.5×10^(-6)℃^(-1).The research demonstrates that the addition of 1.34%dispersant can realize uniform dispersion of M2.5/5 diamond powder in vitrified bond/diamond composites without causing change in properties of the composites.