小型薄壁套管多工位冷镦挤工艺

小型薄壁套管类零件,整体尺寸较小且内外结构复杂,加工方法的选择和成形工艺设计方面是生产该类零件的重点和难点。针对上述难点,采用适合中小型零件批量加工的多工位冷成形加工方法,并根据成形理论分析,初步设计出两种较合理的六工位冷成形方案,对成形过程采用Deform-3D软件数值模拟。得出先反挤压成形薄壁端的最大载荷为5.6×104N,远小于先镦粗成形凸缘的最大载荷;台阶深孔的成形采用杯-杯复合挤压,其损伤值远小于材料的临界损伤值。最终通过生产试验验证模拟结果的最佳工艺,且成形后小型薄壁套管的内部组织分布合理,无冷镦缺陷。

Multi-stage cold forging and extruding process of small thin wall casing

For small thin wall casing parts with a small size but a complex structure,the choice of processing methods and forming process design are main difficulies.In view of the above difficulties,the multi-stage cold forming method suitable for small and medium-sized parts batch processing was proposed,and two more reasonable six-stage cold forging processes was designed based on the forming theory analysis.Then,the forming process was simulated by Deform-3D software,and the maximum load of the thin-walled end 5.6 × 104 N produced by the first anti-extrusion was far less than that produced by first upsetting flange.Furthermore,the deep hole with step was formed by the cup-cup compound extrusion,and the damage value of material was much smaller than that of the critical damage.Finally,the optimal program of simulation results are verified by the production test,and the microstructural distribution is reasonable without cold upsetting defects.