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Resource Efficiency of the Robot-Based Hybrid Additive Manufacturing Chain
Combining additive and subtractive metal processes to a hybrid additive manufacturing chain
not only enables the production of parts with application-oriented design but also leads to
increased resource efficiency especially when combined in an industrial robotic cell.
Compared to parts manufactured through subtractive processes from full material the hybrid
additive manufacturing chain is considered to be resource efficient due to reduced material
consumption. However, the energy consumption of the hybrid additive process is considered
higher because of the use of laser for the additive process.
It is assumed that the decreased material consumption outweighs the higher energy
consumption regarding the resource efficiency but until now it is not investigated. Therefore,
in this paper the resource consumption of the robot-based hybrid additive manufacturing chain
including the wire based direct energy deposition process and the milling process is analysed
through measurements during experiments and compared to subtractive processes using the
carbon footprint as a reference.Mechanical Engineerin
Charcoal kiln sites, associated landscape attributes and historic forest conditions: DTM-based investigations in Hesse (Germany)
The Crystal Structures of a Chiral Aminoalkoxide Cluster and Its Adduct with Benzyllithium
Monomerizing alkali-metal 3,5-dimethylbenzyl salts with tris(N, N -dimethyl-2-aminoethyl)amine (MeTREN) : structural and bonding implications
The series of alkali-metal (Li, Na, K) complexes of the substituted benzyl anion 3,5-dimethylbenzyl (MeCHCH ) derived from 1,3,5-trimethylbenzene (mesitylene) have been coerced into monomeric forms by supporting them with the tripodal tetradentate Lewis donor tris(N,N-dimethyl-2-aminoethyl)amine, [N(CH CHNMe), MeTREN]. Molecular structure analysis by X-ray crystallography establishes that the cation-anion interaction varies as a function of the alkali-metal, with the carbanion binding to lithium mainly in a σ fashion, to potassium mainly in a π fashion, with the interaction toward sodium being intermediate between these two extremes. This distinction is due to the heavier alkali-metal forcing and using the delocalization of negative charge into the aromatic ring to gain a higher coordination number in accordance with its size. MeTREN binds the metal in a η mode at all times. This coordination isomerism is shown by multinuclear NMR spectroscopy to also extend to the structures in solution and is further supported by density functional theory (DFT) calculations on model systems. A MeTREN stabilized benzyl potassium complex has been used to prepare a mixed-metal ate complex by a cocomplexation reaction with tBuZn, with the benzyl ligand acting as an unusual ditopic σ/π bridging ligand between the two metals, and with the small zinc atom relocalizing the negative charge back on to the lateral CH arm to give a complex best described as a contacted ion pair potassium zincate