研究目的
The general objective of this work is to study the small fatigue crack growth behavior in SLM Ti-6Al-4V for various process conditions and in the presence of various porosity defects.
研究成果
The study found that the short fatigue crack growth rates were less than the long fatigue crack growth rates from the surrogate C(T) specimens tested, contrary to expectations. The porosity levels and unique microstructure, leading to crack deflection and multiple cracks bridging events, were attributed to the slower crack growth rates of the short cracks. The samples with the trial build parameters displayed a slower fatigue crack growth rate than the sample with optimized build parameters, possibly due to increased porosity and low hardness values.
研究不足
The study focuses on Ti-6Al-4V specimens produced via selective laser melting, and the findings may not be directly applicable to materials produced by other additive manufacturing techniques or to other titanium alloys. The small sample size and specific build conditions may also limit the generalizability of the results.
1：Experimental Design and Method Selection:
The study utilized in situ synchrotron-based X-ray microtomography (μXSCT) and in situ energy dispersive X-ray diffraction (EDD) to analyze the small fatigue crack growth behavior in SLM Ti-6Al-4V.
2：4V. Sample Selection and Data Sources:
2. Sample Selection and Data Sources: Samples were extracted from broken halves of C(T) specimens previously tested to determine long fatigue crack growth properties of SLM AM Ti-6Al-4V.
3：4V. List of Experimental Equipment and Materials:
3. List of Experimental Equipment and Materials: A custom-made, portable load frame was used for in-situ loading experiments, compatible with the rotational stages used at the APS beamlines.
4：Experimental Procedures and Operational Workflow:
Samples were cyclically loaded to initiate a crack using a servo-hydraulic MTS load-frame, followed by in situ μXSCT and EDD characterization.
5：Data Analysis Methods:
The crack growth rates were analyzed using a 7-point incremental polynomial method, and the applied stress intensity factor range was determined with results from a Finite Element model.
独家科研数据包，助您复现前沿成果，加速创新突破
获取完整内容
