钛合金四层板结构超塑成形/扩散连接工艺

Superplastic forming and diffusion bonding for four-sheet structure of titanium alloy

对Ti2AlNb钛合金四层板夹层结构超塑成形/扩散连接(SPF/DB)进行研究,模拟分析板料在成形过程中的等效应变和壁厚分布规律,优化了压力-时间曲线,为实验提供理论指导和压力加载依据;采用Ti2AlNb热轧板进行SPF/DB实验,对比分析不同工艺参数对成形效果的影响。结果表明,当采用优化的压力-时间曲线进行超塑成形加载,且扩散连接的温度940℃、时间180min、压力10MPa时,成形效果良好,直立加强筋处扩散连接充分,接头处的焊合率达到90%。

The superplastic forming/diffusion bonding （SPF/DB） of four‐sheet sandwich structure of Ti2 AlNb alloy is studied . The equivalent strain distribution and the thickness distribution of SPF/DB process are predicted by simulation .The optimized p‐t curve is obtained which provides theoretical guidance for the experiments and basis for loading pressure design .The SPF/DB ex‐periments are carried out by using Ti2 AlNb hot‐rolled sheets ,and the influences of different parameters on forming quality are compared and analyzed .The results show that the forming quality is well by using the optimized p‐t curve and the optimal diffu‐sion bonding parameters of T=940℃ , p=10MPa and t=180min ,.The vertical stiffeners are completely bonded and the bonding rate is 90% .