TC4钛合金固体渗硼及渗硼过程动力学研究

采用固体粉末渗硼法对TC4钛合金基体表面在1000,1050和1100℃分别保温5,10,15,20h进行了渗硼层厚度的测试,做出了硼钛化合物层生长动力学曲线,并用SigmaPlot10.0对实验数据进行分析和拟合,得出了渗硼层等厚度图.通过SEM与XRD研究TC4钛合金渗硼后的组织形貌和物相组成.结果表明,在实验条件下,渗层由TiB2和伸向基体的须状的TiB组成,渗层厚度范围为0.8～15μm.经回归分析得到硼在钛合金中的平均扩散激活能为65.23kJ/mol.

Pack Boronizing of TC4 Titanium Alloy and Kinetics of Boronizing Process

Pack boronizing process was done on the surface of TC4(Ti-6Al-4V) alloy at 1 000, 1 050 and 1 100℃, each was holding for 5, 10, 15 and 20 h, separately. Then, the boronized layer thickness was tested and the curves of growing kinetics of the B-Ti compound layer were therefore given. Based on analyzing and fitting the test data with the software Sigma Plot 10.0, an isopach chart of boronzied layer was obtained. By XRD and SEM, the phase composition, microstructure and morphology of TC4 titanium alloy after boronizing were investigated. The results showed that the boronzied layer is composed of TiB_2 and whiskerized TiB extending into matrix. Under such testing conditions, the layer thickness is in the range from 0.8 to 15μm. After a linear regression analysis, the average diffusive activation encrgy of boron in the TC4 titanium alloys is 65.23 kJ/mol.