Equiatomic and near-equiatomic NiTinol alloys, mainly due to the exhibition of adjustable mechanical and thermal shape memory properties, are widely exploited to produce different smart and functional devices. Laser powder bed fusion technique was used in this research to process dense NiTinol parts from a prealloyed near-equiatomic NiTi powder, using three different volumetric energy densities. In the next step, samples, processed using a specific set of printing parameters, were annealed using two different procedures. Effects of different used processing volumetric energy densities and post-processing heat treatments on the microstructural properties, phase composition, crystallographic information, phase transformation behavior and hardness of the processed samples were investigated. As-printed Parts with Ni contents ranging from 55.12 to 55.27 wt%, density higher than at least 96% of theoretical and a similar phase structure as that of used powder, dominated by austenitic NiTi, were obtained. Applying a hot isostatic processing treatment at 1100 °C for 4 h or annealing the samples in a pressureless sintering furnace, working under a vacuum environment at the same temperature and holding time, had significant effects on the properties of the printed parts. These treatments, in addition to increasing the density of the printed samples, their average grain size and reducing the residual stresses, shifted the phase transformations to lower temperatures. These results suggest that post-printing heat treatments affect and, as similar to NiTinol alloys having Ni contents above 55.7 wt%, can be used as a strategy to alter the phase transformation temperatures of printed less Ni-rich near-equiatomic NiTinol alloys and consequently obtain NiTinol parts suitable for different applications.

等原子和近等原子的镍钛诺尔合金，主要是由于展现出可调节的机械和热形状记忆特性，因此被广泛用于生产不同的智能和功能设备。在这项研究中，使用激光粉末床熔融技术，使用三种不同的体积能量密度，从预合金化近等原子的NiTi粉末加工致密的NiTinol零件。下一步，使用两种不同的程序对使用一组特定的打印参数处理的样品进行退火。研究了不同使用的处理体积能量密度和后处理热处理对被处理样品的微观结构，相组成，晶体学信息，相变行为和硬度的影响。Ni含量在55.12至55之间的印刷零件。获得了27wt％的密度，其密度高于理论值的至少96％，并且具有与所用粉末相似的相结构，该相结构以奥氏体NiTi为主。在1100°C下进行热等静压处理4 h或在无压烧结炉中对样品进行退火，在相同温度和保持时间下在真空环境下工作，对印刷零件的性能产生重大影响。这些处理方法除了增加打印样本的密度，平均晶粒尺寸和减少残余应力外，还将相变转移到较低的温度。这些结果表明，印刷后的热处理影响且类似于镍含量高于55.7 wt％的镍钛诺合金，