FDM filaments with unique segmentation since evolution: a critical review

The urge towards faster and sophisticated manufacturing is a nurturing factor of human life. Researchers envisage in developing complex products in shorter time duration. The conventional subtractive manufacturing undergoes pre-processing, processing, and post-processing stages. Additive manufacturing (AM) undergoes the same set of stages, where as raw material is added gradually to get the final product in contradiction to the subtractive manufacturing. There are many variants in AM technology, amongst that fused deposition modeling (FDM) is less sophisticated and incurs lesser manufacturing cost. The filament is the deciding factor for the final quality and cost of the product in FDM. Filament invariants have evolved slowly since the 1980s and had shown imperative growth in the last decade. Hence, the significance of filament in FDM insists to undergo a critical review on filament segmentation, growth, and its future. The absence of specific article or publication presenting a review is the prime objective of the critical review.