Oxygen and nitrogen have been both known to have a strong hardening effect on Ti and its alloys, while also imposing a serious embrittlement effect. In the present work, Ti samples with non-uniformly dispersed oxygen and nitrogen solid solutions were produced using high purity Ti via powder metallurgy (PM) methods. The experimental results suggested that, when the solutes are non-uniformly distributed, the high solute content region can serve as strengthening particles as that in metal matrix composites. In light of this, we propose a design of novel structure in high oxygen/nitrogen Ti materials to achieve both improved strengths and ductility. The highlight of the structure is a design of strain gradient at the matrix-particle interface, which can mitigate the strain compatibility that commonly reported in general MMCs as the crack initiator. Instead of using ceramics as reinforcements, here we propose to use the matrix phase itself that hardened by high oxygen/nitrogen solutes as reinforcing particles.

氧和氮都对钛及其合金具有很强的硬化作用，同时还具有严重的脆化作用。在本工作中，通过粉末冶金（PM）方法使用高纯度Ti生产了氧和氮固溶体分散不均匀的Ti样品。实验结果表明，当溶质分布不均匀时，高溶质含量区域可作为金属基复合材料中的强化颗粒。有鉴于此，我们提出了一种在高氧/氮钛材料中的新颖结构设计，以实现更高的强度和延展性。该结构的亮点是在基体-颗粒界面处的应变梯度设计，可以减轻通常在一般MMC中作为裂纹引发剂报告的应变相容性。