Cr-Based Sputtered Decorative Coatings for Automotive Industry

The present work aims to study the impact of O and N addition on Cr-sputtered coatings on plastic (polycarbonate, PC) used in automobile parts, as a promisor alternative for auto part metallization, while eliminating the usage of toxic hexavalent chromium. The coatings were deposited using DC magnetron sputtering from a single pure Cr target in a reactive atmosphere (N2 and/or O2). The deposition of the coatings was performed maintaining the total pressure constant and close to 1 Pa by tuning Ar pressure while reactive gases were added. The target current density was kept at JW = 20 mA·cm−2. Structural characterization revealed a mixture of α-Cr, δ-Cr, β-Cr2N, and CrN crystalline structures as well as amorphous oxides. The coating hardness ranged from 9 GPa for the CrON coating to 15 GPa for the CrN coating. All deposited coatings showed a particularly good interface adhesion; adjusting the amount of O and N made it possible to tune the optical properties of the Cr-based coatings as desired. The promising results open future industrialization of sputtered Cr-based coatings for automotive industries.

CHARACTERISTIC OF MODERN POLYMER MATERIALS AND THEIR APPLICATION IN THE AUTOMOTIVE INDUSTRY

The article describes the advantages of using modern polymer materials for the manufacture of auto parts in the automotive industry. The authors have developed and presented a systematization of modern polymer materials, which are most often used in the automotive industry for the manufacture of both body and engine compartment (under hood) parts, and parts for internal equipment of a car. The studies made it possible for the authors to introduce a characteristic of the modern polymer materials properties that could to be used for the manufacture of a particular car part, as well as indicate brief chemical names (abbreviations) of polymer materials and their compositions (taking into account the requirements of world practice), indicating some properties, namely: heating resistance, solubility in organic solvents, etc. It is indicated that the use of polymer materials in the automotive industry is based directly on the properties of the polymer material and the requirements for a particular auto part. In one of the tables, a list of polymer materials and parts that are made of a certain type of polymer material is outlined, in another table the information on feedback regarding the variation of polymer materials in the process of manufacturing a specific car part is gathered. Special attention is paid to the example of deciphering the stamp meaning, which is stamped on the inner surface of some polymer parts. The stamp reflects information on the type of polymer material from which the auto part is made, the presence of fillers and amplifiers in its composition, as well as their percentage. In addition, a list of the main types of modified polypropylene, a brief designations of polypropylene various modifications and their application in the automotive industry are presented. For the ease of use while forensic practice, the information on the properties and possibilities of using the most commonly used polymer materials in the automotive industry is summarized in table.

Manufacture material characteristic analysis of original and alternative auto parts. Case Study: Brake Disc

All powered vehicles have a braking system adopted according to the type of vehicle and work for which they are designed. In Ecuador, there is a great variety of auto parts that are proposed as alternative replacement, varying in cost and quality. This research aims to quantitatively analyze the characteristics of the brake disc material between original and alternate auto parts. This research analyzes three brake disc samples (A, B, C) from different manufacturing sources, using the ASTM E415-08 spectrometry test and the metallography test under the ASTM A247-16A standard. The spectrometry detects 15 elements in each sample, the carbon equivalent of sample A is 18% and 20% higher in relation to sample B and C, which significantly influences the microstructure. The metallographic tests indicate a pearlitic matrix in each sample, however, there is a different distribution and size of the graphite flakes. According to the SAE J431 standard, each auto part meets the material conditions for the brake disc function.

Investigation of Hydroforming Technology for Manufacturing an Auto Complex Part

Hydroforming process is used for obtaining different kinds of sheet metal components in an economic manner in terms of time and costs reduction and increase of the product quality. This paper deals with the application of this type of technology for manufacturing a rotational auto part from aluminium alloy. An experimental tool for hydroforming with rubber membrane was used. A set of dies with different geometries has been designed and constructed. Experiments have been conducted for investigation the ability of transferring features from the die onto the blank surface for different die geometries and pressures. The hydroformed part was measured using CMM. Based on the experimental data a numerical model was designed. FEM using Abaqus solver was used for investigated the part geometry and the effective stress distribution under various pressures conditions and dies geometries. The experimental and simulation results show the feasibility of applying the sheet hydroforming process in order to obtain a sound product.