Materialien & Produktionstechnik
Refine
Year of publication
Document Type
- Article (149)
- conference proceeding (article) (55)
- Part of a Book (13)
- conference proceeding (presentation) (9)
- Report (3)
- conference proceeding (proceeding) (2)
- Other (2)
- Book (1)
- Preprint (1)
Language
- English (189)
- German (45)
- Multiple languages (1)
Reviewed
Keywords
- Schneckengetriebe (7)
- Fiber optics (6)
- Holzbau (4)
- Optische Polymerfaser (4)
- Sensors (4)
- Sustainability (4)
- Tribologie (4)
- diamond (4)
- Flexible Electronics (3)
- Hybrid Electronics (3)
Institute
- Institut für Chemie, Material- und Produktentwicklung (82)
- Fakultät für Elektrotechnik Feinwerktechnik Informationstechnik (59)
- Fakultät Maschinenbau und Versorgungstechnik (55)
- Fakultät Verfahrenstechnik (48)
- Polymer Optical Fiber Application Center (33)
- Fakultät Werkstofftechnik (29)
- Fakultät Angewandte Mathematik, Physik und Allgemeinwissenschaften (14)
- Partikeltechnologien, Rohstoffinnovationen und Ressourceneffizienz (9)
- Fakultät für Angewandte Chemie (8)
- Fakultät Architektur (6)
Epoxy resins exhibit good mechanical and thermal properties. Most commercially available epoxy resins rely on fossil resources, which is why research is being conducted on the synthesis of bio‐based alternatives. Although many scientists dealt with new bio‐based epoxy resins, there are still only a few publications on new bio‐based amine curing agents. Vanillin is a promising substance for the synthesis of amine curing agents due to its aromatic structure in combination with its potential bio‐origin from lignin. In this article, the synthesis of 3‐amino‐4,5‐dimethoxy‐benzylamine (ADBA) from vanillin and its use as a novel curing agent for epoxy resins is presented. The synthesis comprises four stages: nitration of the aromatic compound vanillin, methylation of the phenolic group, conversion of the aldehyde into an oxime, and hydrogenation to form the diamine. The diamine can be synthesized with a total yield of 51 wt% and a bio‐content of 74 wt%. According to DSC, the new hardener with diglycidyl ether of bisphenol A (DGEBA) shows a gradual curing reaction due to the presence of an aliphatic and an aromatic amine. Glass transition temperatures (Tg) of 135°C were determined via DMA when using ADBA, which is comparable to that of DGEBA cured with IPDA.
Mechanochemical synthesis is frequently identified as a sustainable alternative to solvent-based methods, yet empirical data regarding the energy consumption of various milling platforms remains scarce. This study provides an assessment of the electrical power demand and chemical productivity across five distinct milling modes: vibratory, planetary, media-free, high-energy, and disc milling. We demonstrate that manufacturer reported power specifications consistently overestimate actual operational demand by up to a factor of 3.1x which can lead to inaccuracies in sustainability metrics. Through the investigation of two diagnostic probe reactions, we observed that power consumption is primarily determined by the mechanical inertia and
frequency of the hardware-the platform's "Energy Fingerprint"-with the internal chemical payload exerting a negligible effect. The results show that increasing operational frequency beyond a certain threshold results in disproportionately high energy consumption relative to the incremental gains in chemical yield. By integrating yield and measured power into an energetic
return metric (mmol/kWh), we compare the efficiency of different platforms at the laboratory scale. Furthermore, we observe that the fixed electrical overhead of high-capacity hardware, such as disc and planetary mills, becomes more efficient as reaction volumes increase. This work
provides a standardized framework of measured energy values, enabling more accurate Life Cycle Assessments and supporting the optimization of mechanochemical processes for industrial applications.
Reflow soldering of printed flexible low-cost electronics continues to pose a challenge, which is hampering the growth of the technology. The specific process parameter requirements severely limit the available soldering technologies. This study focuses on the suitability of a new photonic soldering process based on individually controllable near-infrared light emitting diodes (NIR LEDs) for processing screen-printed silver (Ag) structures and etched copper (Cu) structures on polyethylene terephthalate (PET) with low-temperature solders of the Tin-Bismuth-Silver (SnBiAg) group. The approach enabled various component sizes to be successfully soldered under more favorable conditions. An analysis of the shear strength shows comparable behavior for the copper structures compared to samples that were convectively soldered. A significant improvement in the shear strength of the printed silver structures was achieved using the new NIR process.
Non- to minor destructive end-of-life disassembly is a prerequisite for high-value material recovery and component reuse in the circular economy. Yet companies lack a standardized device-level metric to evaluate whether or to what extent disassembly can be automated, especially for electronic devices with heterogenous connection elements (CoEls). This paper introduces a framework consisting of a Disassembly Capability Maturity Model (DCMM) and a resulting Automation Readiness Index (ARI), a key figure to assess automation feasibility for the disassembly of electronic devices. The DCMM rates products’ CoEl sets with phase-specific indicators on a five-level maturity scale, while the ARI aggregates these ratings into a single device-level score. A case study on two cordless vacuum cleaners validates the approach. The results show that the method is easy to apply in practice, sensitive to subtle design differences, and yields consistent, comparable outcomes. By guiding design teams towards targeted, incremental improvements, the framework supports product developers, while the quantification of automation feasibility and the highlighting of critical structural challenges support disassembly planners. This framework provides a structured basis for both comparing disassemblability as well as introducing Design-for-Disassembly (DfD) principles, thereby advancing towards more circular, automated disassembly practices for electronic products.
Manufacturing companies have a strong impact on climate change due to their immense degree of greenhouse gas emissions. Hence, it is mandatory that these companies take measures to reduce their greenhouse gas emissions. A promising measure is the reduction of the carbon footprint caused by single processes within manufacturing process networks. Various approaches to reduce the carbon footprint of single manufacturing processes have already been described in literature. However, there is a scientific need for action when it comes to the systematic reduction of the carbon footprint of queueing systems which are typically an integral element of manufacturing process networks. Therefore, this paper presents a novel approach that aims to assess and reduce the carbon footprint of manufacturing queueing systems systematically. First, a general queueing system is defined and its variables that contribute to the carbon footprint in manufacturing are determined. Subsequently, a mathematical model is designed which enables an abstract description of the interactions of different input variables on the carbon footprint of queueing systems in manufacturing. Afterwards, recommendations to reduce the carbon footprint of queueing systems are developed based on the previous findings. Finally, the approach is validated for a specific manufacturing queueing system with a discrete-event simulation study. The results give foundations for further research on dependencies within manufacturing process networks.
This file contains a script for determining band gaps from DRS measurements using a semi-automatic approach to eliminate potential user bias during the fitting procedure. The methods are based on the publications from J. Tauc, Materials Research Bulletin, vol. 3, no. 1, Jan. 1968 and P. Makuła, et al., The Journal of Physical Chemistry Letters, vol. 9, no. 23, Dec. 2018.
This work compares three experimental methods for determining the rotation angle and position of polarization-maintaining fibers for use in integrated fiber arrays: detection of the front-face panda structure, polarization measurements of the light guided by the fiber, and imaging the panda structures via the lateral view of the fiber. Position and rotational angle of the PM fiber are detected via image recognition algorithms. Achieved positional accuracies lie in the sub-micrometer range, rotational accuracies in the range of 0.01 rad corresponding to a polarization extinction ratio of > 40 dB.
As part of the Bavarian research project BayWater, which focuses on the use of membrane technologies for sustainable industrial water treatment, we are working with the IWC at TUM on an advanced oxidation process (AOP) based on peroxydisulfate (S2O82-). This process is intended to be used as a pre-treatment for wastewater in reverse osmosis (RO) plants, with the aim of minimizing membrane fouling. In addition to the low binding energy of peroxydisulfate (120 kJ·mol–1) and the associated high activation efficiency, peroxydisulfate offers advantages in terms of safety, storage stability and the associated costs. One way to activate and thus generate sulfate radicals from peroxydisulfate is by irradiation with light, especially in the UV range. The oxidation performance can be controlled via the optical power of the sources used in a way that minimizes fouling without damaging the membrane. For this reason, the aim is to design an AOP flow reactor using powerful UV LEDs on the basis of laboratory tests. Peroxydisulfate exhibits much higher extinction in the UVC region, which favors UVC activation. UVA LEDs, however, are significantly more energy-efficient, making them attractive from an operational standpoint. Therefore, the choice of the most suitable AOP light source should be based on experimental data. The radical-production efficiency of UV activation will be analyzed using a liquid-chromatography–based method and evaluated by the number of radicals generated per unit of energy consumed. The results will contribute to evaluating the feasibility of employing UV LEDs in AOP applications as an alternative to traditional mercury lamps.
This study valorizes granite sawing waste and kaolin through production of durable ceramics tiles. FactSage (8.4) thermochemical software was integrated with petrography, XRD, XRF, DTA-TGA, SEM-EDX, physico-mechanical, hot-stage microscopy, dilatometry, chemical durability tests and Raman spectroscopy to investigate the green materials and ceramics sintered at 900-1250 °C/h. Results show that Al/Si, Ca/Si, and Ca/Al ratios and impurities levels control feldspar crystallization, glassy phase formation, and the development of silicate melt with variable viscosities. The optimum composition (40 wt% granite waste at 1200 °C/h) has a compact, interlocked microstructure with ∼47 wt% melt and suitable viscosity (2.41 × 105 PaS), yielding negligible water absorption (0.19%), low porosity (0.46%), high flexural strength (52 MPa), controlled thermal expansion (5.42 × 10−6 C−1), and excellent acidic/alkali durability (0.48, 0.06 wt%) as well as acceptable geometric stability. However, 50 wt% granite waste involvement caused deformation at 1200 °C, and bloating occurring at 1250 °C. Ceramic tiles at 1200 °C are promising for heavy-duty industrial flooring applications.
