CIRP JOURNAL OF MANUFACTURING SCIENCE AND TECHNOLOGY, vol.37, pp.302-311, 2022 (SCI-Expanded)
Additive manufacturing (AM) has been a breakthrough revolution in the
manufacturing world due to the ability to economically print parts with high
geometric complexity, minimal vast and dissimilar materials in the same
printing process. However, some problems arise with the usage of
multi-materials in AM machines. This study aims to analyze the scheduling
problem of a single AM machine for printing multi-material parts. We developed
a mathematical model for a single AM machine to directly minimize the makespan
of a production schedule of multi-material parts and indirectly minimize the
material changeovers. IBM ILOG CPLEX Optimization Studio (v12.10) is used for
the development stage of the model. Some numerical examples from AM literature
were handled and solutions were gathered. Effects of material changeover costs
for the different numbers of materials were investigated. Results indicated
that setup time depending on material changeovers
becomes a critical parameter for the minimization of makespan. Higher
numbers of dissimilar materials increase the completion time of the schedule.
While the developed model can be used for AM machines with different material
changeover difficulties, it can also be used in the printing of parts that need
to be uncontaminated finished products.