The current work evaluates cross-sectioned green bilayer powder compact (green BPC) of iron (Fe) under different die conditions. At first, finite element-based (FE) simultaneous compaction modelling is used to model the uniaxial, one-sided compaction of the green BPC of Fe and its interface. A Tri-mesh of 0.03 mm and mesh refinement along the interfacial boundary is set up with the condition of each node from both sides of layers (namely lower layer, L and upper layer, U) is mapped precisely to ensure its mutual interconnection along the horizontal edges of interface. Additionally, the modelling part utilised and validated our recently proposed image analysis under the metallographic technique’s standard framework. Our approach to model the interface to gain the same effect as from the experimental result of green BPC of Fe is in good agreement. It is significantly found that the use of the lubricated die condition contributed to increasing the local RD distribution along the interface of the green BPC of Fe. In contrast, the distribution is gradually dissuaded from the interface for the unlubricated die condition as the applied height: diameter (H:D) ratio increases.

• Abebe, A., Akseli, I., Sprockel, O., Kottala, N., & Cuitiño, A. M. (2014). Review of bilayer tablet technology. International Journal of Pharmaceutics, 461(1-2), 549-558. https://doi.org/10.1016/j.ijpharm.2013.12.028

• Arifin, A., Gunawan, G., & Yani, I. (2022). Plagiarism and similarity checker of porous titanium alloy/hydroxyapatite composite using powder compaction route. Turnitin Universitas Sriwiajaya. https://repository.unsri.ac.id/66950/

• Bellini, M., Walther, M., & Bodmeier, R. (2019). Evaluation of manufacturing process parameters causing multilayer tablets delamination. International Journal of Pharmaceutics, 570, Article 118607. https://doi.org/10.1016/j.ijpharm.2019.118607

• Boonyongmaneerat, Y., & Schuh, C. A. (2006). Contributions to the interfacial adhesion in co- sintered bilayers. Metallurgical and Materials Transactions A, 37(5), 1435-1442. https://doi.org/10.1007/s11661-006-0088-9

• Brewin, P. R., Coube, O., Doremus, P., & Tweed, J. H. (2008). Modelling of Powder Die Compaction (Vol. 329). Springer.

• Canta, T., & Frunza, D. (2003). Friction-assisted pressing of PM components. Journal of Materials Processing Technology, 143-144, 645-650. https://doi.org/10.1016/S0924-0136(03)00475-8

• Castrati, L., Mazel, V., Busignies, V., Diarra, H., Rossi, A., Colombo, P., & Tchoreloff, P. (2016). Comparison of breaking tests for the characterization of the interfacial strength of bilayer tablets. International Journal of Pharmaceutics, 513(1-2), 709-716. https://doi.org/10.1016/j.ijpharm.2016.10.005

• Chang, S. Y., & Sun, C. C. (2019). Effect of particle size on interfacial bonding strength of bilayer tablets. Powder Technology, 356, 97-101. https://doi.org/10.1016/j.powtec.2019.07.100

• Chávez, J., Jiménez Alemán, O., Flores Martínez, M., Vergara-Hernández, H. J., Olmos, L., Garnica-González, P., & Bouvard, D. (2020). Characterization of Ti6Al4V–Ti6Al4V/30Ta bilayer components processed by powder metallurgy for biomedical applications. Metals and Materials International, 26(2), 205-220. https://doi.org/10.1007/s12540-019-00326-y

• Chen, W., Wang, J., Wang, S., Chen, P., & Cheng, J. (2020). On the processing properties and friction behaviours during compaction of powder mixtures. Materials Science and Technology (United Kingdom), 36(10), 1057-1064. https://doi.org/10.1080/02670836.2020.1747779

• Cristofolini, I., Molinari, A., Pederzini, G., & Rambelli, A. (2018). From experimental data, the mechanics relationships describing the behaviour of four different low alloyed steel powders during uniaxial cold compaction. Powder Metallurgy, 61(1), 10-20. https://doi.org/10.1080/00325899.2017.1361507

• Edosa, O. O., Tekweme, F. K., & Gupta, K. (2022). A review on the influence of process parameters on powder metallurgy parts. Engineering and Applied Science Research, 49(3), 433- 443.

• El-Nasr, A. A., Saleh, A., & Alshennawy, A. A. (2020). Porosity measurement of iron oxide by using computer vision system. International Journal of Engineering Research and Technology, 13(4), 653-659.

• Elsayed, M. M., Aboelez, M. O., Mohamed, M. S., Mahmoud, R. A., El-Shenawy, A. A., Mahmoud, E. A., Al-Karmalawy, A. A., Santali, E. Y., Alshehri, S., Elsadek, M. E. M., El Hamd, M. S., & Ramadan, A. E. H. (2022). Tailoring of rosuvastatin calcium and atenolol bilayer tablets for the management of hyperlipidemia associated with hypertension: a preclinical study. Pharmaceutics, 14(8), Article 1629.

• Favrot, N., Besson, J., Colin, C., & Delannay, F. (1999). Cold Compaction and Solid-State Sintering of WC-Co-Based Structures: Experiments and Modeling. Journal of the American Ceramic Society, 82(5), 1153-1161. https://doi.org/10.3390/pharmaceutics14081629

• Grigoriev, S. N., Dmitriev, A. M., Korobova, N. V., & Fedorov, S. V. (2019). A cold-pressing method combining axial and shear flow of powder compaction to produce high-density iron parts. Technologies, 7(4), 2-17. https://doi.org/10.3390/technologies7040070

• Hasan, M., Zhao, J., Huang, Z., Wei, D., & Jiang, Z. (2019). Analysis and characterization of WC- 10Co and AISI 4340 steel bimetal composite produced by powder-solid diffusion bonding. The International Journal of Advanced Manufacturing Technology, 103(9), 3247-3263. https://doi.org/10.1007/s00170-019-03709-y

• Kulkarni, H., & Dabhade, V. V. (2019). Green machining of powder-metallurgy-steels (PMS): An overview. Journal of Manufacturing Processes, 44, 1-18. https://doi.org/10.1016/j.jmapro.2019.05.009

• Masooth, P. H. S., Bharathiraja, G., Jayakumar, V., & Palani, K. (2022). Microstructure and mechanical characterisation of ZrO2 reinforced Ti6Al4V metal matrix composites by powder metallurgy method. Materials Research Express, 9(2), Article 020003. https://doi.org/10.1088/2053-1591/ac5352

• Mihalcea, E., Vergara-Hernández, H. J., Jimenez, O., Olmos, L., Chávez, J., & Arteaga, D. (2021). Design and characterization of Ti6Al4V/20CoCrMo− highly porous Ti6Al4V biomedical bilayer processed by powder metallurgy. Transactions of Nonferrous Metals Society of China, 31(1), 178- 192. https://doi.org/10.1016/S1003-6326(20)65486-3

• Ojo-kupoluyi, O. J., Tahir, S. M., Hanim, M. A., Anuar, M. S., & Dele-Afolabi, T. T. (2019). Investigating the effect of sintering temperature on the microstructure and hardness of cemented tungsten carbide/steel bilayer. IOP Conference Series: Materials Science and Engineering, 469(1), Article 012020. https://doi.org/10.1088/1757-899X/469/1/012020

• Radchenko, A. K. (2004). Mechanical properties of unsintered pressings. I. phenomenological relations for unsintered pressing strength. Powder Metallurgy and Metal Ceramics, 43(9), 447-460. https://doi.org/10.1007/s11106-004-0003-0

• Rajab, M., & Coleman, D. S. (1985). Density distributions in complex shaped parts made from iron Powders. Powder Metallurgy, 28(4), 207-216.

• Rowe, J. M., & Nikfar, F. (2017). Modeling approaches to multilayer tableting. In P. Pandey & R. Bharadwaj (Eds.), Predictive Modeling of Pharmaceutical Unit Operations (pp. 229-251). Woodhead Publishing. https://doi.org/10.1016/B978-0-08-100154-7.00009-0

• Santos, T. D. E. D. S., Regiani, I., Rocha, R. J., & Rocco, J. A. F. F. (2018). Copper/iron brake friction for military aircraft application. Journal of Aerospace Technology and Management, 10, Article e2018. https://doi.org/10.5028/jatm.v10.834

• Sinka, C. (2007). Modelling powder compaction. KONA Powder and Particle Journal, 25, 4-22. https://doi.org/10.14356/kona.2007005

• Sopchak, N. D., & Misiolek, W. Z. (2000). Density gradients in multilayer compacted iron powder parts. Materials and Manufacturing Processes, 15(1), 65-79. https://doi.org/10.1080/10426910008912973

• Thomazic, A., Guennec, Y. L., Kamdem, Y., Pascal, C., Chaix, J. M., Doremus, P., Imbault, D., Bouvard, D., & Doré, F. (2010, October 10-14). Fabrication of bimaterial components by conventional powder metallurgy. [Paper presentation]. In Proceedings of the International Powder Metallurgy World Congress & Exhibition, Florence, Italy.

• Wang, J. Z., Qu, X. H., Yin, H. Q., Yi, M. J., & Yuan, X. J. (2009). High velocity compaction of ferrous powder. Powder Technology, 192(1), 131-136. https://doi.org/10.1016/j.powtec.2008.12.007

• Wang, L., Wang, D., Huang, S., Guo, X., Wan, G., Fan, J., & Chen, Z. (2019). Controllable shape changing and tristability of bilayer composite. ACS Applied Materials & Interfaces, 11(18), 16881-16887. https://doi.org/10.1021/acsami.8b21214

• Yohannes, B., Gonzalez, M., Abebe, A., Sprockel, O., Nikfar, F., Kiang, S., & Cuitiño, A. M. (2017). Discrete particle modeling and micromechanical characterization of bilayer tablet compaction. International Journal of Pharmaceutics, 529(1-2), 597-607. https://doi.org/10.1016/j.ijpharm.2017.07.032

• Yuan, X., Qu, X., Yin, H., Feng, Z., Tang, M., Yan, Z., & Tan, Z. (2021). Effects of sintering temperature on densification, microstructure and mechanical properties of al-based alloy by high-velocity compaction. Metals, 11(2), Article 218. https://doi.org/10.3390/met11020218

• Yusoff, S. M., Tahir, S. M., Hanim, M. A. A., Supeni, E. E., & Anuar, M. S. (2021). Fabrication and evaluation of density distribution in green bilayer iron powder compact. Materials and Manufacturing Processes, 36(6), 660-667. https://doi.org/10.1080/10426914.2020.1854474

• Zadeh, H. K. (2010). Finite Element Analysis and Experimental Study of Metal Powder Compaction. Queen’s University.