Ghadimi Hamed, Jirandehi Arash P, Nemati Saber, Ding Huan, Garbie Abdelrahman, Raush Jonathan, Zeng Congyuan, Guo Shengmin
Department of Mechanical and Industrial Engineering, Louisiana State University, Baton Rouge, LA 70803, USA.
Department of Mechanical Engineering, University of Louisiana at Lafayette, Lafayette, LA 70503, USA.
Materials (Basel). 2023 Jan 4;16(2):469. doi: 10.3390/ma16020469.
In this paper, small blocks of 17-4 PH stainless steel were manufactured via extrusion-based bound powder extrusion (BPE)/atomic diffusion additive manufacturing (ADAM) technology in two different orientations. Ultrasonic bending-fatigue and uniaxial tensile tests were carried out on the test specimens prepared from the AM blocks. Specifically, a recently-introduced small-size specimen design is employed to carry out time-efficient fatigue tests. Based on the results of the testing, the stress-life (S-N) curves were created in the very high-cycle fatigue (VHCF) regime. The effects of the printing orientation on the fatigue life and tensile strength were discussed, supported by fractography taken from the specimens' fracture surfaces. The findings of the tensile test and the fatigue test revealed that vertically-oriented test specimens had lower ductility and a shorter fatigue life than their horizontally-oriented counterparts. The resulting S-N curves were also compared against existing data in the open literature. It is concluded that the large-sized pores (which originated from the extrusion process) along the track boundaries strongly affect the fatigue life and elongation of the AM parts.
在本文中，通过基于挤压的粘结粉末挤压（BPE）/原子扩散增材制造（ADAM）技术，以两种不同的取向制造了17-4PH不锈钢小块。对由增材制造块制备的试样进行了超声弯曲疲劳和单轴拉伸试验。具体而言，采用了最近引入的小尺寸试样设计来进行高效的疲劳试验。基于测试结果，在超高周疲劳（VHCF） regime中创建了应力-寿命（S-N）曲线。通过对试样断口表面进行的断口分析，讨论了打印取向对疲劳寿命和拉伸强度的影响。拉伸试验和疲劳试验的结果表明，垂直取向的试样比水平取向的试样具有更低的延展性和更短的疲劳寿命。还将所得的S-N曲线与公开文献中的现有数据进行了比较。得出的结论是，沿轨迹边界的大尺寸孔隙（源于挤压过程）强烈影响增材制造零件的疲劳寿命和伸长率。
