6
Remanufacturing and Advanced Machining
As far as selection of technology is concerned, the fuzzy logic approach can be
applied in order to minimize vagueness in decision-making, thereby making results
more similar to experts’ thinking. Kafuku et al. (2019) evaluated and ranked appropriately six cleaning technologies, using criteria of technology cost, operating cost, and
disposal effect. The fuzzy approach revealed that technology performance is largely
impacted by criteria far beyond the technology itself, including purchasing cost, disposal cost, operating cost, and other support functions. Despite the fact that decisionmakers can select a technology appropriately, the application of the fuzzy logic tool
helps to accommodate vagueness, ambiguity, and subjective views of experts.
Application of remanufacturing to industry has an immense impact on costs and
environment which is possible to assess. For example, Xiao et al. (2018) used life
cycle analysis to compare environmental impacts and cost of a newly manufactured
loading machine (S1) with its counterparts remanufactured at the original factory
(S2) and at regional dealers (S3). It was demonstrated that the financial cost in S2
and S3 scenarios was 48% and 35%, respectively, of the cost in S1, while the climate
change impacts in a functional unit decreased by 72% and 80% in S2 and S3, respectively. Apparently, remanufacturing in both scenarios still has a better environmental
and economic performance than manufacturing a new product.
In the following chapters, we will emphasize techniques and processes especially
suitable for new materials and remanufacturing. Remanufacturing is totally different from the other EoL strategies as a product is restored to like new condition with
reduced waste generation and less resource consumption. As a result, a significantly
higher profit margin for producers is achieved due to reduced production cost and
environmentally proactive benefits (Fegade et al., 2015).
1.2 FOAM INJECTION MOLDING
Introduction of pores into traditional materials is one of the novelties in material sciences and applications. As such, porous materials are a class of functional-structural
materials with an optimal index of physical and mechanical properties and they
include metals, ceramics, and polymers (Liu and Chen, 2014). Wood may be considered the oldest form of foam, since it is a naturally occurring foam of cellulose,
but the first commercial foam was sponge rubber that was introduced in the 1910s
(Ebnesajjad, 2003).
Technology of the foam molding has been known for more than 40 years, but it is
continuously improved and modified. Some injection molding technologies facilitate
more sustainable production, while others allow the production of components with
new structures and properties, but foam injection molding offers the potential to
combine both (Kastner et al., 2020). It is no wonder that the casting of various polymer materials with different sorts of structural foaming is attracting even more attention with time. Compared to bulky polymer materials, polymer foam exhibits low
density, good heat insulation, good sound insulation effects, high specific strength,
and resistance to corrosion (Jin et al., 2019). Foamed plastics may be flexible, semirigid, or rigid, and their densities may range from 1.6 to over 960 kg/m 3 (Rosato
et al., 2004). In addition, they display easy recyclability, a better warpage behavior,
Remanufacturing and Advanced Machining
As far as selection of technology is concerned, the fuzzy logic approach can be
applied in order to minimize vagueness in decision-making, thereby making results
more similar to experts’ thinking. Kafuku et al. (2019) evaluated and ranked appropriately six cleaning technologies, using criteria of technology cost, operating cost, and
disposal effect. The fuzzy approach revealed that technology performance is largely
impacted by criteria far beyond the technology itself, including purchasing cost, disposal cost, operating cost, and other support functions. Despite the fact that decisionmakers can select a technology appropriately, the application of the fuzzy logic tool
helps to accommodate vagueness, ambiguity, and subjective views of experts.
Application of remanufacturing to industry has an immense impact on costs and
environment which is possible to assess. For example, Xiao et al. (2018) used life
cycle analysis to compare environmental impacts and cost of a newly manufactured
loading machine (S1) with its counterparts remanufactured at the original factory
(S2) and at regional dealers (S3). It was demonstrated that the financial cost in S2
and S3 scenarios was 48% and 35%, respectively, of the cost in S1, while the climate
change impacts in a functional unit decreased by 72% and 80% in S2 and S3, respectively. Apparently, remanufacturing in both scenarios still has a better environmental
and economic performance than manufacturing a new product.
In the following chapters, we will emphasize techniques and processes especially
suitable for new materials and remanufacturing. Remanufacturing is totally different from the other EoL strategies as a product is restored to like new condition with
reduced waste generation and less resource consumption. As a result, a significantly
higher profit margin for producers is achieved due to reduced production cost and
environmentally proactive benefits (Fegade et al., 2015).
1.2 FOAM INJECTION MOLDING
Introduction of pores into traditional materials is one of the novelties in material sciences and applications. As such, porous materials are a class of functional-structural
materials with an optimal index of physical and mechanical properties and they
include metals, ceramics, and polymers (Liu and Chen, 2014). Wood may be considered the oldest form of foam, since it is a naturally occurring foam of cellulose,
but the first commercial foam was sponge rubber that was introduced in the 1910s
(Ebnesajjad, 2003).
Technology of the foam molding has been known for more than 40 years, but it is
continuously improved and modified. Some injection molding technologies facilitate
more sustainable production, while others allow the production of components with
new structures and properties, but foam injection molding offers the potential to
combine both (Kastner et al., 2020). It is no wonder that the casting of various polymer materials with different sorts of structural foaming is attracting even more attention with time. Compared to bulky polymer materials, polymer foam exhibits low
density, good heat insulation, good sound insulation effects, high specific strength,
and resistance to corrosion (Jin et al., 2019). Foamed plastics may be flexible, semirigid, or rigid, and their densities may range from 1.6 to over 960 kg/m 3 (Rosato
et al., 2004). In addition, they display easy recyclability, a better warpage behavior,