氮化硼纤维热处理工艺对其性能影响的研究

Influence of Heat Treatment on the Performances of Boron Nitride Fibers

以硼酸为原料．分别在氨气（NH3）和氮气（N2）气氛下进行氮化．制备氮化硼纤维。用中和滴定法、扫描电镜、XRD等对氮化硼纤维的氮含量、形貌、拉伸强度、弹性模量等进行分析。结果表明，氨气气氛下970℃保温1h和在氮气气氛下2000℃保温1h制得的氮化硼纤维的直径在4～6μm．氮含量为54．36％．拉伸强度为1400MPa．弹性摸量为120CPa。

In this study, boron nitride （BN） fibers were prepared via chemical method using boric acid as the ray. material, under the atmosphere of NH3 anti N2 , respectively. Firstly. the borie acid was heated to meh in order to acquire B2O3 fibers. Seconedly, the B2O3 fibers were pre - azotized under a NH3 atmosphere and hehl for 1 h at 970 ℃, and the sample was then sintered in N2 to the temperature of 2 000 ℃ and hehl for 1 h. The obtained samples were texted to analyze nitrogen content, morphology, tensile strength, and elastic modnlus by neutralization titration. SEM, XRD and so on. The resuhs show , that the diameter of the BN fibers is 4 - 6 ,μm with Ihe nitrogen content of 54.36%, tensile strength of 1 400 MPa. and elastic modulus of 120 GPa.