INFLUENCE OF THE GRADIENT ZONE EXTENT OF THE FUNCTIONAL GRADIENT PRODUCT OF THE CU/AL SYSTEM ON THE STRUCTURAL-PHASE STATE AND MECHANICAL PROPERTIES

The formation of functional gradient Cu/Al materials with a continuous intermetallic surface layer by electron beam additive manufacturing is associated with the formation of a number of inhomogeneities and defects in the structure. The main obstacles to obtaining stable and defect-free FGM structures on the surface of the copper base are the difference in the coefficients of thermal expansion of copper and aluminum at the boundary with the formation of intermediates, cracks and delaminations. The formation of a smooth gradient from copper to intermetallic Cu/Al layers allows to avoid the formation of cracks and delaminations. In the work, defect-free functional gradient Cu/Al materials with different gradient zone widths were obtained using electron beam additive technology. The structural-phase state and mechanical properties of FGM Cu/Al over the entire height of the printed material are investigated. It is established that the Cu/Al gradient zone of FGM consists of the phases α-Cu, Cu₄Al, Cu₃Al and Cu₉Al₄. It is established that the width of the gradient zone affects the volume fraction of CuxAly intermetallic phases, which, in turn, determine the magnitude of the elongation at a constant value of the tensile strength (305 ± 10 MPa). The microhardness values increase sharply in the gradient zone and have an uneven distribution due to the formation of Cu4Al, Cu3Al and Cu9Al4 intermetallides. It is shown that the upper part of the Cu/Al FGM, consisting of 67 % Cu and 33 % Al (vol.), demonstrates a sharp drop in mechanical properties, which is probably due to the formation of the Cu9Al4 phase, the volume fraction of which prevails compared to other intermetallic phases of the Cu_xAl_y system.

1. Utyaganova V, Filippov A., Tarasov S., Shamarin N., Gurianov D., Vorontsov A., Chumaevskii A., Fortuna S., Savchenko N., Rubtsov V., Kolubaev E. Characterization of AA7075/AA5356 gradient transition zone in an electron beam wire-feed additive manufactured sample. Materials Characterization. 2021, vol. 172, article 110867.

2. Chmielewski M., Pietrzak K. Metal-ceramic functionally graded materials–manufacturing. Technical sciences. 2016, vol. 64, no. 1, pp. 151–160.

3. Niendorf T., Leuders S., Riemer A., Brenne F., Tröster T., Albert Richard H., Schwarze D. Functionally Graded Alloys Obtained by Additive Manufacturing. Advanced engineering materials. 2014, vol. 16, pp. 857–861.

4. Muller P., Hascoet J.-Y., Mognol P. Toolpaths for additive manufacturing of functionally graded materials (FGM) parts. Rapid Prototyping Journal. 2014, vol. 20, no. 6, pp. 511–522.

5. Yi Su, Bo Chen, Caiwang Tan, Xiaoguo Song, Jicai Feng. Influence of composition gradient variation on the microstructure and mechanical properties of 316L/Inconel718 functionally graded material fabricated by laser additive manufacturing. Journal of Materials Processing Technology. 2020, vol. 283, article 116702.

6. Ghanavati R., Naffakh-Moosavy H. Ad-ditive manufacturing of functionally graded metallic materials: A review of experimental and numerical studies. Journal of Materials Research and Technology. 2021, vol. 13, pp. 1628–1664.

7. Domack M.S., Baughman J.M. Development of Nickel-Titanium Graded Composition Components. Rapid Proto. J. 2004, vol. 11, no. 1, pp. 41–51.

8. Matsuo S., Watari F., Ohata N. Fabrication of a functionally graded dental composite resin post and core by laser lithography and finite element analysis of its stress relaxation effect on tooth root. Dent. Mater. J. 2021, vol. 20, no. 4, pp. 257–274.

9. Kawasaki A., Watanabe R. Thermal fracture behavior of metal/ceramic functionally graded materials. Eng. Fract. Mech. 2002, vol. 69, pp. 1713–1728.

10. Niino M., Kisara K., Mori V. Feasibility study of FGM technology in space solar power systems (SSPS). Mater. Sci. Forum. 2005, vol. 492, pp. 163–170.

11. Loh G.H., Pei E., Harrison D., et al. An overview of functionally graded additive manufacturing. Addit. Manuf. 2018, vol. 23, pp. 34–44.

12. Mahamood R.M., Akinlabi E.T., Shukla M., et al. Functionally graded material: an overview. Proc. World Cong. Eng. 2012, vol. 3.

13. Naebe M., Shirvanimoghaddam K. Functionally graded materials: A review of fabrication and properties. Appl. Materials Today. 2016, vol. 5, pp. 223–245.

14. Zhe Sun, Yuan-Hui Chueh, Lin Li. Mul-tiphase mesoscopic simulation of multiple and functionally gradient materials laser powder bed fusion additive manufacturing processes. Additive Manufacturing. 2020, vol. 35, article 101448.

15. Xiaoji Zhang, Yuan-hui Chueh, Chao Wei, Zhe Sun, Jiwang Yan, Lin Li. Additive manufacturing of three-dimensional metal-glass functionally gradient material components by laser powder bed fusion with insitu powder mixing. Additive Manufacturing. 2020, vol. 33, article 101113.

16. Huang J., Liu G., Yu X., Wu H., Huang Y., Yu S., Fan D. Micro-structure regulation of titanium alloy functionally gradient materials fabricated by alternating current assisted wire arc additive manufacturing. Materials & Design. 2022, vol. 218, article 110731.

17. Chumaevskii A., Kalashnikova T., Gusarova A., Knjazhev E., Kalashnikov K., Panfilov A. The Structure Organization and Defect Formation of Cu-Al System Polymetallic Materials Produced by the Electron-Beam Additive Technology. In: 7th International Congress on Energy Fluxes and Radiation Effects (EFRE). 2020, pp. 1294–1298.

18. Osipovich K.S., Astafurova E.G., Chu-maevskii A.V., et al. Gradient transition zone structure in “steel-copper” sample produced by double wire-feed electron beam additive manufacturing. J. Mater Sci. 2020, vol. 55, pp. 9258–9272.

19. Oliveira J.P., Crispim B., Zeng Z., Omori T., Braz Fernandes F.M., Miranda R.M. Micro-structure and mechanical properties of gas tungsten arc welded Cu-Al-Mn shape memory alloy rods. Journal of Materials Processing Technology. 2019, vol. 271, pp. 93–100.

20. Koteswara Rao S.R., Madhusudhana Reddy G., Kamaraj M., Prasad Rao K. Grain refinement through arc manipulation techniques in Al-Cu alloy GTA welds. Materials Science and Engineering: A. 2005, vol. 404, pp. 227–234.

21. Galvão I., Loureiro A., Rodrigues D.M. Critical review on friction stir welding of aluminium to copper. Sci. Technol. Weld. Join. 2016, vol. 21, no. 7, pp. 523–546.

22. Zhang H., Liu Xu., Zhang B., Guo Y. Enhancing the mechanical performances of friction stir lap welded Al-Zn-Mg-Cu alloy joint by promoting diffusion of alloying element Zn toward the pre-positioned Cu interlayer. Materials Science and Engineering: A. 2022, vol. 832, pp. 142467.

23. Paidar M., Elveny M., Mehrez S., Ravi S., Babaei B., Ravichandran M. Influence of material positioning during modified friction stir clinching brazing of Al/Zn/Cu welds. Materials Letters. 2021, vol. 301, article 130250.

24. Liu H., Zuo Y., Ji S., Dong J., Zhao H. Friction stir solid-liquid spot welding of Cu to Al assisted by Zn interlayer. Journal of Materials Research and Technology. 2022, vol. 18, pp. 85–95.

25. Su H., Zhao Q., Chen Ji., Wu C. Homogenizing the intermetallic compounds distribution in Al/Cu dissimilar friction stir welding joint with the assistance of ultrasonic vibration. Materials Today Communications. 2022, vol. 31, article 103643.

26. Zhao Y., You J., Qin J., Dong C., Liu L., Liu Z., Miao S. Stationary shoulder friction stir welding of Al-Cu dissimilar materials and its mechanism for improving the microstructures and mechanical properties of joint. Materials Science and Engineering: A. 2022, vol. 837, article 142754.

27. Shankar S., Chattopadhyaya S., Mehta K.P., Vilaca P. Influence of copper plate positioning, zero tool offset, and bed conditions in friction stir welding of dissimilar Al-Cu alloys with different thicknesses. CIRP Journal of Manufacturing Science and Technology. 2022, vol. 38, pp. 73–83.

28. Chumaevskii A.V., Panfilov A.O., Knyazhev E.O., Zykova A.P., Gusarova A.V., Kalashnikov K.N., Vorontsov A.V., Savchenko N.L., Nikonov S.Y., Cheremnov A.M., Rubtsov V.E., Kolubaev E.A. Production of Gradient Intermetallic Layers Based on Aluminum Alloy and Copper by Electron–beam Additive Technology. In: Diagnostics, Resource and Mechanics of materials and structures, 2021, pp. 19–31.

29. Zykova A.P., Panfilov A.O., Chumaevskii A.V., Vorontsov A.V., Nikonov S.Yu., Mos-kvichev E.N., Gur'yanov D.A., Savchenko N.L., Tarasov S.Yu., Kolubaev E.A. Features of the formation of the microstructure and mechanical properties of aluminum bronze with different heat input during electron beam additive printing. Izvestiya vuzov. Fizika. 2022, no. 5, pp. 45–51. (In Russ.).