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This work consists of evaluating the influence of heat treatment on sintered valve seat insert (VSI) obtained with two different high-speed steels powders and one tool steel: AISI M3:2, AISI M2 and AISI D2, respectively. The high-speed / tool steel powders were mixed with iron powders and additives such as manganese sulphide, zinc stearate, graphite and niobium carbide. All the high-speed / tool steel powders had its particle size distribution and morphology analyzed. The heat treatment of the VSI consisted of air quenching followed by double tempering it in seven different and equidistant temperatures, ranging from 100 °C until 700 °C. A data acquisition system with a thermocouple type k attached to the samples was used to determine the air-quenching cooling rate. The mechanical and physical properties measurements were carried out, i.e., apparent density, apparent hardness and crush radial strength.

Studying the formation and distribution of residual stress fields will improve the wheel safety operational criteria among other gains. Many engineering specifications, manufacturing procedures, inspection and quality control have begun to require that the residual stress of a particular component to be evaluated. It is known that these residual stress fields could be added to the effects of a system load (tare weight plus occupation of vehicle, traction, braking and torque combined). The mathematical tools for modeling and simulations using finite elements had evolved following the increasing computing power and hardware cost reduction. On the other hand, the experimental testing, offers specific physical component behavior and with the use of statistical tools, it is possible to predict the real behavior of the component when in operation. The experiments undertaken used the X-ray diffraction technique and the drilling method with rosette type strain gages.

This paper reports the experimental efforts in recording the 2-dimensional temperature distribution on autogenous thin plates of UNS S32304 steel during welding. The butt-welded autogenous joints were experimentally performed by the GTAW (Gas Tungsten Arc Welding) process with either argon or argon-2%nitrogen atmospheres. The temperatures cycles were recorded by means of thermocouples embedded by spot welding on the plate's surfaces and connected to a multi-channel data acquisition system. The laser flash method (LFM) was also used for the determination thermal diffusivity of the material in the thickness direction. The temperature curves suggest a relationship between the microstructures in the solidified and the heat affected zone with the diffusivity variation. This is a region where there had been a major incidence of heat. The obtained results validate the reliability of the experimental used apparatus.

The vacuum forming process for plastic parts is used to manufacture packages as well as any kind of industrial appliance for a range of sectors, including the automotive industry. This diversity of uses is due to the attractive cost of the process. In the automotive industry, it is a big ally, used as an alternative process in the manufacture of prototype parts. This occurs not only because of the reduction in the time to obtain the part, but also the technical opportunity of product development allowed by this process due to the material that can be used. Some analyses and developments would not be possible if the part were manufactured using the material specified by the part design. This paper shows how the vacuum forming process can facilitate the development of automotive vehicles, as well as a simple and fast way to manufacture vacuum formed parts, which allows parts to be obtained by any kind of industry.

Fiberglass laminated parts are used in automotive industry, especially for limited quantities of parts production. They are useful on prototypes and special vehicles, among other things. If the parts are not laminated with required quality, the result can jeopardize the vehicle parts application. This paper shows a simple manner of vacuum bagging process application for fiberglass and carbon fiber parts lamination with dimensional and surface quality required. It also shows the mould fabrication process and its importance to the laminated parts quality.