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The paper deals with the design and manufacturing of a McPherson suspension arm made from short glass fiber reinforced polyamide (PA66). The design of the arm and the design of the molds have been made jointly. According to Industry 4.0 paradigms, a full digitalization of both the product and process has been performed. Since the mechanical behavior of the suspension arm strongly depends on constraints which are difficult to be modelled, a simpler structure with well-defined mechanical constraints has been developed. By means of such simple structure, the model for the behavior of the material has been validated. Since the suspension arm is a hybrid structure, the associated simple structure is hybrid as well, featuring a metal sheet with over-molded polymer. The issues referring to material flow, material to material contact, weld lines, fatigue strength, high and low temperature behavior, creep, dynamic strength have been investigated on the simple structure.

In this paper the lightweight design and construction of road vehicle aluminum wheels is dealt with, referring particularly to safety. Dedicated experimental tests aimed at assessing the fatigue life behavior of aluminum alloy A356 - T6 have been performed. Cylindrical specimens have been extracted from three different locations in the wheel. Fully reversed strain-controlled and load-controlled fatigue tests have been performed and the stress/strain-life curves on the three areas of the wheel have been computed and compared. The constant amplitude rotary bending fatigue test of the wheel has been simulated by means of Finite Element method. The FE model has been validated by measuring the strain at several points of the wheel during the actual test. From the FE model, the stress tensor time history on the whole wheel over a loading cycle has been extracted.

Many of the materials which have been developed for use as particle filters in the exhaust of diesel engines have characteristics which give rise to significant problems in practical use. Due to its special characteristics, it is shown that SiC is very well suited for use as the base material for particulate filters. The physical and thermal properties of porous SiC substrate material as applied to diesel particulate filters have been determined and are presented. Experimental results from several types of filter regeneration processes in exhaust gas systems confirm the improvements in the area of thermal load and reduction in temperature level during regeneration. The reduction in temperature during regeneration is shown to be consistent with the high thermal conductivity of SiC.

Recent studies have shown that SiC provides substantial advantages for use as the material for wall flow diesel particulate filters. In addition to very advantageous thermal properties, it has been shown that SiC based filter material has higher permeability than Cordierite. This paper presents a comparison of the basic flow characteristics of SiC based and Cordierite based wall flow filter material, expressed in terms of parameters which are basic materials properties that are independent of filter geometry. In addition, the flow characteristics of the particulate matter collected on the filter during engine operation are presented. The results show that the advantageous flow characteristics observed with the basic filter material are retained for loaded filters, up to very high loadings.

Silicon Carbide (SiC) has been shown to have a high melting/decomposition temperature, good mechanical strength, and high thermal conductivity, which make it well suited for use as a material for diesel particulate filters. The high thermal conductivity of the material tends to reduce the temperature gradients and maximum temperature which arise during regeneration. The purpose of this paper is to experimentally investigate the thermal loading which arise under regenerations of varying severity. An experimental study is presented, in which regenerations of varying severity are conducted for uncoated SiC and Cordierite filters. The severity is varied through changes in the particle loading on the filters and by changing the flow conditions during the regeneration process itself. Temperature distributions throughout the filters are measured during these regeneration.

This work presents a comprehensive numerical model for ice accretion and Ice Protection System (IPS) simulation over a 2D component, such as an airfoil. The model is based on the Myers model for ice accretion and extended to include the possibility of a heated substratum. Six different icing conditions that can occur during in-flight ice accretion with an Electro-Thermal Ice Protection System (ETIPS) activated are identified. Each condition presents one or more layers with a different water phase. Depending on the heat fluxes, there could be only liquid water, ice, or a combination of both on the substratum. The possible layers are the ice layer on the substratum, the running liquid film over ice or substratum, and the static liquid film between ice and substratum caused by ice melting. The last layer, which is always present, is the substratum. The physical model that describes the evolution of these layers is based on the Stefan problem. For each layer, one heat equation is solved.

A new bench for the rotating bending fatigue tests of tempered steel wires is presented. The new bench is used to check the spring wire just before it is finally winded to realize a spring. The bench is basically a four-point bending machine. There are two main differences with respect to current bending machines. The first one is that the focus is on semi-finished components (more than 1 meter long), rather than standard small-scale specimens. The second one is that there is a non-linear configuration of the tested component due to its length. The bench design has provided some unreferenced features that make the bench quite accurate and effective in producing quick fatigue assessments. A rotor-dynamic study has allowed to perform tests at 50 Hz. As a preliminary application, some fatigue bending tests of tempered steel wires are described and discussed.

Brake calipers for high-end cars are typically realized using Aluminum alloys, with Silicon as the most common alloying element. Despite the excellent castability and machinability of Aluminum-Silicon alloys (AlSix), anodization is often required in order to increase its corrosion resistance. This is particularly true in Chlorides-rich environments where Aluminum can easily corrode. Even if anodization process is known for almost 100 years, anodization of AlSix -based materials is particularly challenging due to the presence of eutectic Silicon precipitates. These show a poor electric conductivity and a slow oxidation kinetics, leading to inhomogeneous anodic layers. Continuous research and process optimization are required in order to develop anodic layers with enhanced morphological and electrochemical properties, targeting a prolonged resistance of brake calipers under endurance corrosive tests (e.g. >1000 hours Neutral Salt Spray (NSS) tests).

The work investigates the effect of different Iron and Manganese contents in ad-hoc cast specimens made from recycled EN AC-43200 alloy. Tensile tests and metallographic analyses coupled with energy dispersive X-ray spectroscopy measurements are carried out to elucidate the interplay between the microstructure and the quasi-static properties of the Aluminium-Silicon alloy under investigation. A strong correlation between the composition and morphology of Fe/Mn -based intermetallic precipitates and tensile properties is demonstrated. Moreover, it is found that specific intermetallic phases are present only for certain, relative and/or absolute contents of Fe and Mn.

To improve torque management algorithms for drivability, the powertrain controller must be able to compensate for the nonlinear dynamics of the driveline. In particular, the presence of backlash in the transmission and drive shafts excites sharp torque fluctuations during tip-in or tip-out transients, leading to a deterioration of the vehicle drivability and NVH. This paper proposes a model-based estimator that predicts the wheel torque in an automotive drivetrain, accounting for the effects of backlash and drive shaft flexibility. The starting point of this work is a control-oriented model of the transmission and vehicle drivetrain dynamics that predicts the wheel torque during tip-in and tip-out transients at fixed gear. The estimator is based upon a switching structure that combines a Kalman Filter and an open-loop prediction based on the developed model.