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Lattice structures are widely used for achieving optimal topology in additive manufacturing. However, the use of different lattices in a single design can result in stress concentrations at the transition points. This study aims to investigate the influence of Bezier curves on mechanical properties during the transformation from one lattice structure to another. It specifically focuses on the transition from a hexagonal to diamond lattice, using Bezier curves of various orders.

The curves were designed by passing them through the same control points for different orders, such as third, fifth and seventh. The samples were sliced for 3D printing, and a tensile test was conducted. Young’s modulus and energy absorption abilities were measured to compare the mechanical properties of the models created with Bezier curves for the transformation between hexagonal and diamond models.

The analysis revealed a gradual change in mechanical properties from the hexagonal to the diamond lattice. Moreover, different orders of Bezier curves exhibited varying mechanical properties during the transformation between the two lattices. As the order of the Bezier curve increased, the mechanical properties smoothly changed from the hexagonal to diamond lattice. This prevented stress concentrations or mechanical behavior mismatch caused by sudden deformations at the transitions between the curves used in the design.

The study’s innovative use of Bezier curves of different orders to smoothly transformation between hexagonal and diamond lattices in additive manufacturing offers a practical solution to prevent stress concentrations and mechanical inconsistencies during such design transitions.

By drawing on ethnographic fieldwork conducted amongst waste-pickers and recycling traders in the waste paper, plastic and scrap metal sectors, and engaging with literature from economic anthropology and history, as well as archival sources, this paper documents changing perceptions of just price, morality and fairness in the Turkish recycling market. The paper suggests that multiple markets imply multiple prices, which are contingent and contested. When dealing with price mechanisms largely outside their control, actors tend to associate a fair price with the going market price, rather than factors such as state regulation. Approaches to morality and assessments of fairness become more ambiguous when prices are mediated by actors’ own practices. These range from gift relations to paternalism, envy and deception.