Critical factor triggering grain boundary cracking in non-weldable superalloy Alloy713ELC fabricated with selective electron beam melting
| Autor: | Kinya Aota, Yuchao Lei, Akihiko Chiba, Kosuke Kuwabara, Kenta Aoyagi |
|---|---|
| Rok vydání: | 2021 |
| Předmět: |
010302 applied physics
Electron-beam additive manufacturing Materials science Polymers and Plastics Metals and Alloys 02 engineering and technology Plasticity 021001 nanoscience & nanotechnology 01 natural sciences Thermal expansion Electronic Optical and Magnetic Materials Superalloy Cracking 0103 physical sciences Ceramics and Composites Grain boundary Process window Composite material 0210 nano-technology Liquation |
| Zdroj: | Acta Materialia. 208:116695 |
| ISSN: | 1359-6454 |
| Popis: | Grain boundary cracking in non-weldable superalloy fabricated with selective electron beam melting is affected by the interaction of multiple factors including mechanical and compositional effects. In this study, we construct process maps in a wide range high-dimensional parameter space for the non-weldable superalloy Alloy713ELC through employing a machine learning approach, and we could fabricate many cracked and crack-free samples under the optimized conditions by excluding the extrinsic effect of process defects on cracking. Comparing between cracked and crack-free samples reveals that the samples with fine columnar grains can be cracked while those with coarse columnar grains can be crack-free, and that the cracking propensity in the optimized samples within a process window with scan speed ≤ 800 mm/s can be ranked by using a quasi-total plastic strain index (QTPSI), which is calculated via thermo-mechanical analysis. The total plastic strain level is a critical cracking factor and a larger scan speed tends to elevate the total plastic strain level, exhibiting a larger deviation beyond the QTPSI. Besides, the non-weldability in Alloy713ELC significantly attributes to its thermal expansion effect, which correlates to the large Al content. This thermal expansion effect combined with the liquation effect and the strain-age cracking effect reveals the intrinsic cause of non-weldability in Alloy713ELC. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect