Aiming to obtain a martensite-free microstructure of Ti–Zr alloys with a combination of enhanced deformability and improved mechanical properties for dental application, two high Zr-containing Ti-based alloys were prepared with commercially pure titanium as a control. The effects of Zr addition on the deformation mechanism, microstructure and mechanical properties were investigated. After thermo-mechanical processing and cold deformation, samples were characterized using Vickers microhardness, tensile tests, X-ray diffraction (XRD) scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The XRD and TEM examinations revealed that the increasing Zr addition suppressed the deformation twining and favored the deformation-induced face-centered cubic (FCC) phase, the corresponding reason was discussed. There is a competition between the deformation twin and FCC phase. The two types of FCC phase were simultaneously found with orientation relationships (ORs) of Basal-type: <11–20>_HCP//<110>_FCC and {0001}_HCP//{111}_FCC and Prismatic-type: <0001>_HCP//<001>_FCC and {10-10}_HCP//{110}_FCC. This phase transformation enhanced the deformability during processing. As the Zr addition increased, the microhardness, mechanical strength and plasticity are increased concurrently. The interactions of twins were found to cause brittle fracture of Ti20Zr alloy. Based on the texture analysis, the activated slip systems of FCC phase were determined via calculating the Schmid factor. The FCC phase not only provided additional slip systems but also impeded dislocation slip effectively, improving the strength-plasticity of Ti30Zr alloy. The findings will provide a novel approach associated with the strengthening-toughening mechanism of metallic materials.

为了获得具有增强的可变形性和改善的牙科应用机械性能的Ti-Zr合金无马氏体微观结构，制备了两种含Zr的高含Ti Ti基合金，并以商业纯钛为对照。研究了添加Zr对变形机理，微观组织和力学性能的影响。经过热机械处理和冷变形后，使用维氏显微硬度，拉伸试验，X射线衍射（XRD）扫描电子显微镜（SEM）和透射电子显微镜（TEM）对样品进行表征。XRD和TEM检查表明，增加的Zr添加量抑制了变形孪生并有利于形变诱导的面心立方（FCC）相，并讨论了相应的原因。形变孪晶和FCC相之间存在竞争。同时发现两种类型的FCC相具有基本类型的取向关系（OR）：<11–20>_HCP // <110> _FCC和{0001} _HCP // {111} _FCC和棱形类型：<0001> _HCP // <001> _FCC和{10-10} _HCP // {110} _FCC。这种相变增强了加工过程中的可变形性。随着Zr添加量的增加，显微硬度，机械强度和可塑性同时增加。发现孪晶的相互作用引起Ti20Zr合金的脆性断裂。在纹理分析的基础上，通过计算施密特因子确定了催化裂化相的活化滑移系统。FCC相不仅提供了附加的滑移系统，而且还有效地阻止了位错滑移，从而提高了Ti30Zr合金的强度-塑性。这些发现将提供一种与金属材料的增韧机理相关的新颖方法。