钛合金框锻件热锻过程中低倍组织分层及模具磨损行为的数值分析

Numerical Analysis on Die Wear and Macrostructure Delamination Characteristics of Titanium Alloy Frame in Hot Forging

摘要:

TC18钛合金锻件低倍组织出现分层现象。较亮的低倍组织具有较低的性能，通常被称为冷模组织。降低冷却速度可能会减少冷模组织的产生，但也可能加剧模具磨损。通过模拟和实验研究了TC18钛合金框锻件热锻过程低倍组织分层、模具磨损与工艺参数间的关系。通过二次开发将冷模组织和磨损深度预测模型导入DEFORM软件。利用开发后的软件模拟了钛合金框锻件连续锻造生产过程，研究了冷模组织和磨损特性。利用响应面法和优化参数，讨论了不同参数下模具磨损与冷模组织厚度间的关系。结果表明：钛合金锻件冷模组织含量主要受接触条件的影响，而锻模磨损深度主要受模具预热温度的影响。应用玻璃纤维润滑剂能在不显著增加磨损深度的前提下实现锻件冷模缺陷组织含量的有效降低。

Abstract:

The microstructure of TC18 titanium alloy die forging shows delamination. The brighter microstructure has lower performance and is often called cold die microstructure (CDM). Decreasing the cooling rate can hinder the generation of CDM, but it may also aggravate the die wear. The balance relation between microstructure delamination of TC18 frame forging and the die wear in different parameters was studied by simulation and experiment. The programs to predict the CDM and wear depth were built and realized by secondary development. Continuous forging production process was simulated by DEFORM software and the characteristics of CDM and wear were researched. The balance relationship between the die wear and the CDM content in different parameters was discussed by the response surface method and the optimal parameters. Results show that the preheating temperature of die plays a dominant role in the variation of the wear depth. The most influential factor of CDM content is the contact condition. Applying glass fiber can reduce the CDM content without increasing the wear depth.