钛合金TC4热轧板切削异常原因分析及改善措施

Analysis of Abnormality and Its Causes During the Machining Process of TC4 Hot-Rolled Plate and Methods for Improving Its Machining Performance

针对钛合金TC4封装壳体加工异常的现象,从壳体的加工工艺过程、钛合金热轧板材化学成分、金相组织等方面进行了详细分析,判定壳体加工异常的原因在于材料中呈粗大长条状分布的初生α相,并分析了钛合金热轧板材中产生粗大长条状初生α相的原因。在此基础上,研究了采用固溶处理工艺消除热轧板中粗大初生α相工艺方法。试验结果表明,固溶处理可以改善钛合金TC4热轧板的显微组织,使大部分粗大的初生α相分解为细碎的次生等轴α相,明显改善材料的切削加工性能。

Aiming at the abnormality appeared during the machining process of the TC4 shell, a detailed analysis is done about the manufacturing process, the chemical component of plate and the metallurgical structure of the titanium alloy hot-roll plate. It is shown that the cause resulting in the machining abnormality is coarse strip-shaped primary α phase. By analyzing the mechanism causing primary α phase, a solution treatment is adopted to eliminate the primary α phase. Experiment result shows that the solution treatment can improve the machining performance of TC4 material by ameliorating the micro-structure and making majority of the primary α phase decompose to fine equiaxed secondary α phase.