The single-point incremental forming process is an emerging process, which presents an alternative to the conventional sheet metal forming processes like hydroforming and drawing. It is known to be perfectly suited for prototyping and small series. For example, the incremental forming process offers the possibility of manufacturing medical prosthesis or implants specific to each patient, which are more comfortable and guarantee better performance. The customization of this type of product brings better efficiency and better comfort. However, the manufacture of customized titanium prosthesis is not yet industrialized, mainly due to the geometrical inaccuracy of the parts and inability to form parts with a high wall angle. In fact, considerable forces and damage occur during the process limiting the formability. Several studies have already shown that increasing the working temperature allows improving the formability. A reverse engineering approach associated with warm single-point incremental forming process, in order to produce a customized titanium prosthesis, can make the ability to be exploited in the industry to manufacture titanium alloys medical shapes. In this paper, an experimental and numerical study of the warm incremental process based on the use of heat cartridges is performed. The objective is to demonstrate that our low-cost heating system can be used in forming limit angle similar to that obtained with expensive laser heating. The effects of the wall angle at 450 °C on the forming force, thickness distribution and displacement are investigated by producing a truncated cone with Ti–6Al–4V thin sheets. Results show that the formability is significantly improved with the heating. In addition, a thermo-viscoplastic constitutive model is used to simulate the warm incremental forming process. A comparison of the numerical and experimental results shows that the finite element model gives accurate predictions.

单点渐进成形工艺是一种新兴工艺，它是液压成形和拉伸等常规钣金成形工艺的替代方案。众所周知，它非常适合原型设计和小批量生产。例如，渐进成形过程提供了制造针对每个患者的医疗假体或植入物的可能性，这些假体或植入物更舒适并保证更好的性能。定制此类产品可带来更高的效率和更好的舒适度。然而，定制钛假体的制造尚未工业化，这主要是由于零件的几何形状不精确以及无法形成具有高壁角的零件。实际上，在该过程中会发生相当大的力和损坏，从而限制了可成形性。多项研究已经表明，提高工作温度可以改善可成形性。为了生产定制的钛假体，与温暖的单点渐进成形工艺相关的逆向工程方法可以使工业生产钛合金医用形状的能力得到提高。在本文中，对基于加热盒的热增量过程进行了实验和数值研究。目的是证明我们的低成本加热系统可用于形成极限角，类似于使用昂贵的激光加热获得的极限角。通过生产带有Ti-6Al-4V薄板的截锥，研究了450°C的壁角对成形力，厚度分布和位移的影响。结果表明，随着加热，可成形性显着提高。另外，使用热粘塑性本构模型来模拟热增量成型过程。数值和实验结果的比较表明，有限元模型给出了准确的预测。