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“Lightweight construction is boring!” Despite its immense explosiveness, this incredibly heretical statement was almost unheard of at a press conference on the fringes of an established automotive industry meeting in Germany. Actually, it’s surprising, since this statement came not just from anybody, but from a very well-known German automobile expert.
Prof. Ferdinand Dudenhöffer knows what he is talking about. A few weeks earlier, his institute, the CAR (Center of Automotive Research), had carried out a series of quite simple driving tests. Two electric cars, the BMW i3 compact car and the Tesla S sedan started the race. Both vehicles were tried several times on a 100 km test track. The energy consumption in the empty state, with only the driver on board, was analysed and with additional weight loads of 100, 200 and 300 kg each – these were gravel-filled bags. The result was surprising: the weight of the vehicle has hardly any effect on the range of electric cars.
“The Tesla needed 17.77 kilowatt hours (kWh) of electricity on the 100-km test track with the driver at the wheel (...). However, if you add 100 kg of gravel, the consumption even drops to a minimum of 17.67 kWh.
With 300 kg of river pebbles, the Model S requires 17.87 kWh. At this point you are in the range of measuring tolerances; the maximum increase in consumption is 0.6 %.”* The CAR researchers explain the test result with recuperation, the energy recovery during braking. The recovered energy during the test in the empty i3 was 3.62 kWh, with an additional load of 300 kg the value was significantly higher at 4.17 kWh. This recuperation effect compensates for at least part of the excess consumption with additional weight. According to CAR, Tesla’s value was even higher than that of the small BMW.
Stop with the Carbon Credo?!
Has this heralded the end of the fasting period for the automotive industry? For years, the lightweight dogma for e-mobility was preached quasi ex cathedra everywhere, and OEMs invested millions in carbon technologies. These dietary cravings sometimes sprouted bizarre blossoms when plastic manufacturers boasted that their polymer solutions for metal substitution had a major impact on the development of e‑mobility and they considered themselves not too good for claiming weight savings of components in the low double-digit gram range as milestones.
There is no doubt that there is still a whole series of mobility concepts in which the subject of lightweight construction should be given top priority. But at least in electro mobility a paradigm shift is on the horizon.
Lighter = faster? Wrong again!
Are you at least faster if you are out and about as a light-weight? Not always! This is for example not the case if you are sitting in a glider and want to take part in a competition. Then you should fill the tanks in the ultra-light carbon fibre wings with water to optimize the gliding characteristics for higher speed.
While I am writing this, a mechanical wall clock is ticking quietly in the background. The beautiful piece based on a kit is still in the adjustment phase. And what should I tell you? If you want to accelerate the course of the clock, because it is slow, you have to... yes, quite right! place additional weight on the middle of the pendulum.
* Welt am Sonntag, 49, 3 December 2017
The global tire industry is seeing the first evidence of huge changes affecting the business environment. There are at least five separate aspects, each of which would bring challenges, but together they amount to a radical transformation in the industry. The rubber product manufacturing industry – and especially the tire industry – has a reputation for being highly conservative. If tire industry leadership is to steer their companies through the coming changes, management attitudes are going to have to change away from risk-averse to embracing change. This article describes the changing industry and arising challenges like managing people, shift of focus away from technology as well as systems supply and cultural flexibility.
Dielectric elastomers (DEs) constitute an increasingly important category of electroactive polymers, a class of generally soft materials that, upon exposure to an electric stimulus, respond by changing size and/or shape. Derived from network-forming macromolecules, DEs are lightweight, robust and scalable, and they are furthermore capable of exhibiting giant electroactuation strains, high electromechanical efficiencies, and relatively low strain-cycling hysteresis over a broad range of electric fields. Due primarily to their attractive electromechanical attributes, DEs are of growing interest in diverse biomedical, (micro)robotic, and analytical technologies. Since the seminal studies of these electroresponsive materials (initially fabricated mainly from chemically crosslinked acrylic and silicone elastomers), advances in materials design over multiple length scales have resulted in not only improved electromechanical performance but also better mechanistic understanding. In this work, we first review the fundamental operating principles of DEs developed from conventional elastomers that undergo isotropic electroactuation and then consider more recent advances at different length scales. At the macroscale, incorporation of oriented fibers within elastomeric matrices is found to have a profound impact on electroactuation by promoting an anisotropic response. At the mesoscale, physically crosslinked thermoplastic elastomer gel networks formed by midblock-swollen triblock copolymers provide a highly tunable alternative to chemically crosslinked elastomers. At the nanoscale, the chemical synthesis of so-called “binetwork” and bottlebrush elastomers permits extraordinarily enhanced electromechanical performance through targeted integration of inherently prestrained macromolecular networks.
Robust quantitative crosslink density characterization becomes necessary for the complete understanding of the structure and optimization of final properties of rubber compounds for industrial applications. A combination of different experimental techniques have been used to establish the quantitative consistency on the correlations between the results obtained by the individual methods within a reliable unique (physically based) platform reclined on the concept of rubber elasticity that considers the impact of entanglements in technical rubbers. The contribution of crosslinks and elastically active entanglements to mechanical properties has been quantified by the analysis of uniaxial stress-strain measurements by means of the extended tube model of rubber elasticity. In a complementary manner, rubber network structure has also been investigated by state-of-the-art multiple-quantum low-field NMR experiments and classical T1 and T2 relaxation measurements. In addition, equilibrium swelling data were analyzed by the classical phantom and Flory-Rehner limits, as well as by applying the theoretical approach proposed by Helmis, Heinrich, and Straube that takes into account topological constraints during swelling. Correlations among these complementary techniques have been reported, and the interpretation of the obtained differences is addressed. The baseline study focuses on unfilled NR, setting the basis for the investigation of unfilled SBR matrices and filled rubbers.
Dow Performance Silicones has recently released an innovative product line of fluorinated liquid silicone rubber (FLSR) that offers all the processing advantages of typical LSR and the fluid resistant properties of fluorosilicone rubber (FSR). It is widely known that fluorinated silicones are useful in meeting the sealing requirements in many automotive and aerospace applications. Lord Corporation offers innovative technologies in IMB (in-mold bonding) adhesives for overmolding of LSR to a thermoplastic and metal component. Mixing this polymeric adhesive, in this case IMB 3010 parts A and B and IMB 3000 parts A and B, applying it to the substrate is all that is needed to prepare the surface for bond formation. With light weighting of components so critical to fuel savings, many designs seek to integrate a fluid resistant elastomer (soft) to a lighter weight thermoplastic or metal (rigid) substrate. A study using two grades of FLSR, Silastic FL 40-9201 and Silastic FL 60-9201, bonded to several types of thermoplastic: Ultem PEI, Radel PPSU, and Veradel PESU; and metal substrates: aluminum and steel, explores the durability of these composites. Comparisons are made in bond strength per ASTM D429 method B (and other test methods) after exposure to heat, fuel swell, and steam. Surface structures of the bond formation are examined and considered as further detailed understanding of the chemical structure of the substrate-to-adhesive and adhesive-to-rubber interfaces.
The Center of Automotive Management (CAM) at the University of Applied Sciences in Bergisch Gladbach (FHDW) regularly analyses the sales developments and trends in the field of electro mobility in key automotive markets as well as innovations of car manufacturers. Since 2005, the CAM examines sales trends and overall conditions in relevant countries as well as technological innovations of more than 30 car groups. Over 10,000 innovations are currently inventoried in the CAM “Inno-database”. Each individual innovation is systematically evaluated and weighted according to the M.O.B.IL approach (maturity level, originality, benefit for customer, innovation level). The innovation strength of an automobile manufacturer is calculated from the sum of the weighted innovations. The following report presents the results of a CAM study that analysed the current market trends and product strategies of global automakers in the period from January to December 2017.
ContiTech Schlauch GmbH, a division of Continental, is a specialist in manufacturing automotive and industrial hoses. Since 2006, the company situated in Korbach, Germany, has been using Sikora X-ray measuring systems in its plants for quality control during the extrusion of brake hoses. The cooperation between both companies is based on a solution for automated quality control in the inline process.
Chinaplas 2018 will be held for the first time at the National Exhibition and Convention Center (NECC) in Hongqiao, Shanghai, from 24 – 27 April 2018. The organiser Adsale expects the exhibition area to exceed 320,000 m2. This would be 30 % more exhibition space than that of the 2016 edition of the show in Shanghai. 4,000 exhibitors from around the world are expected to register for the event. They will be allocated over a series of theme zones, among them a dedicated TPE and rubber zone.
The Italian Plastics and Rubber Processing Machinery and Moulds Manufacturers Association (Amaplast) has issued its annual market analysis and forecast. The industry association sees a positive trend that continues unabated in the Italian import-export market for plastics and rubber processing machinery, equipment and moulds.