Molybdenum (Mo) and its alloys are one of the refractory material groups of interest for additive manufacturing (AM), as they meet the requirements for some applications in aerospace and medical industries. The present research and development work aims to develop the proper parameter sets for pure Mo and its alloys, such as Mo-47.5Re wt% and characterize their microstructure and mechanical properties. Primary parameter optimization of the laser power, point distance, exposure time, and hatch distance were tested using a design of experiments to optimize the relative density of the specimens for the Laser Powder Bed Fusion (L-PBF) metal AM technology. Test specimens with relative densities of >98% were successfully fabricated for both pure Mo and Mo-47.5Re wt%. Mechanical testing and microstructural characterization were conducted on the specimens. Microcracking is present in both pure Mo and Mo-47.5Re wt%. Persistence of cracking in the Re containing alloy can be attributed to higher concentration of oxygen in the fabricated samples. A significant increase in strength and compressive ductility was observed in AM fabricated Mo-47.5Re wt% as compared to the pure Mo samples. Solidification texture randomization was also observed in Mo-47.5Re wt%, for which the underlying mechanism is not yet understood. This provides an encouraging outlook to continue testing and developing Mo and its alloys on a L-PBF platform with further stress reduction and material development strategies.

钼 (Mo) 及其合金是增材制造 (AM) 感兴趣的耐火材料组之一，因为它们满足航空航天和医疗行业的某些应用的要求。目前的研究和开发工作旨在为纯钼及其合金（如 Mo-47.5Re wt%）开发合适的参数集，并表征其微观结构和机械性能。使用实验设计对激光功率、点距离、曝光时间和孵化距离的主要参数优化进行了测试，以优化激光粉末床融合 (L-PBF) 金属 AM 技术样品的相对密度。对于纯 Mo 和 Mo-47.5Re wt%，成功制造了相对密度 >98% 的测试样品。对试样进行机械测试和微观结构表征。微裂纹存在于纯 Mo 和 Mo-47.5Re wt% 中。含铼合金中裂纹的持续存在可归因于制造样品中较高的氧浓度。与纯 Mo 样品相比，在 AM 制造的 Mo-47.5Re wt% 中观察到强度和压缩延展性显着增加。在 Mo-47.5Re wt% 中也观察到凝固织构随机化，其潜在机制尚不清楚。这为继续在 L-PBF 平台上测试和开发 Mo 及其合金提供了令人鼓舞的前景，并进一步降低了应力和材料开发策略。含铼合金中裂纹的持续存在可归因于制造样品中较高的氧浓度。与纯 Mo 样品相比，在 AM 制造的 Mo-47.5Re wt% 中观察到强度和压缩延展性显着增加。在 Mo-47.5Re wt% 中也观察到凝固织构随机化，其潜在机制尚不清楚。这为继续在 L-PBF 平台上测试和开发 Mo 及其合金提供了令人鼓舞的前景，并进一步降低了应力和材料开发策略。含铼合金中裂纹的持续存在可归因于制造样品中较高的氧浓度。与纯 Mo 样品相比，在 AM 制造的 Mo-47.5Re wt% 中观察到强度和压缩延展性显着增加。在 Mo-47.5Re wt% 中也观察到凝固织构随机化，其潜在机制尚不清楚。这为继续在 L-PBF 平台上测试和开发 Mo 及其合金提供了令人鼓舞的前景，并进一步降低了应力和材料开发策略。其潜在机制尚不清楚。这为继续在 L-PBF 平台上测试和开发 Mo 及其合金提供了令人鼓舞的前景，并进一步降低了应力和材料开发策略。其潜在机制尚不清楚。这为继续在 L-PBF 平台上测试和开发 Mo 及其合金提供了令人鼓舞的前景，并进一步降低了应力和材料开发策略。