Cu-Sn-Ti体系边际二元系界面反应的研究

Study on interfacial reactions of Cu-Sn-Ti boundary binary systems

Cu-Sn-Ti三元系及其相关的3个二元系均具有重要的实用价值.实验制备了Ti/Sn和Cu/Sn固-液扩散偶及Cu/Ti二元固相扩散偶,经电子显微和探针观测发现： Ti/Sn固-液扩散偶在873K下退火30～160min,只生成1个Sn3Ti2中间相; Cu/Sn固-液扩散偶在808K下退火10min时也只生成1个Cu3Sn中间相,但退火时间延长至30min时在Cu与Cu3Sn界面上生成Cu41Sn11,退火60min后在Cu与Cu41Sn11之间又生成了bcc-a2; Cu/Ti二元固相扩散偶在1023K下退火1000h后,在其界面处生成了CuTi2、CuTi、Cu4Ti3、Cu4Ti 4个化合物,而Cu3Ti2相并未在扩散偶中出现.还采用最大驱动力模型对上述3个二元系的界面反应过程进行了计算并成功解释了相应的实验现象.

Cu-Sn-Ti ternary system and its related three boundary solid/solid binary systems are of critical importance in practice.Ti/Sn and Cu/Sn solid/liquid diffusion couples and Cu/Ti diffusion couples are prepared and then examined using SEM and EPMA.Only Sn3Ti2 forms if Ti/Sn solid/liquid diffusion couples are annealed at 873 K for 30-160 min.When annealed at 808 K for 10 min,only Cu3Sn forms in Cu/Sn solid/liquid diffusion couple.With the annealed time increasing,Cu41Sn11 layer forms between Cu and Cu3Sn in 30 min, and then bcc-a2 layer formsbetween Cu and Cu411Sn11 in 60 min. After annealing at 1 023 K for 1000 hours, four compounds, CuTi2, CuTi, Cu4 Ti3 and Cu4 Ti form in Cu/Ti diffusion couple while Cu3 Ti2 is absent. The interracial reaction process and phase formation sequence have been predicted with maximum driving force model using Thermo-Calc software.