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According to tribology theories and wear mechanisms, several techniques are used for preventing and reducing wear. In repair-maintenance welding which is one of these methods, surface of main material is covered with wear high resistant hardfacing materials and thus, materials can be used again in industry. The aim of this experimental study is determining of influences of farin (cement's raw material) and clinker (cement's semi finished product) on abrasive wear conditions of wear plates that were coated with hardfacing alloy and used as grinders in cement production. Coatings were deposited onto EU S355JO steel plates with shielded metal arc welding (SMAW) method by using five different commercial hardfacing electrode. Abrasive wear tests were done with dry sand-rubber wheel abrasive wear testing machine according to Procedure A indicated in ASTM G65 test standard. However in wear tests, farin and clinker abrasives were used instead of quartz abrasives which as stated in ASTM G65 standard. Thus, determination of abrasive wear resistances of wear plates were become more realistic. Microstructure examinations were done by using optical microscopy (OM) and scanning electron microscopy (SEM). Additionally, formed phases in hardfacing coatings were determined by X-ray diffraction (XRD) analysis for supporting microstructure examinations. Vickers hardness measurements of coatings were done in room temperature. [ABSTRACT FROM AUTHOR]

The term of "Orthodontia" which is the first statement to identify orthodontics is used in19 th Century. Orthodontics is the study of dentistry that is concerned with the treatment of improper bites, and crooked teeth. Orthodontic treatment can help fix your teeth and set them in the right place. After a course of active orthodontic treatment, patients will typically wear retainers, which maintain the teeth in their improved positions while surrounding bone reforms around them. Stainless steel, titanium alloys and cobalt-chromium alloys are widely used orthodontic applications. In addition to high mechanical properties, their corrosion resistance is very important for each alloy system. The aim of this study is to investigate the influence of artificial saliva solution (Fusuyama solution) after a period of the time (14-28 days) on metallic wires (NiTi, β-Ti and Fe-Cr-Ni based orthodontic wires) widely used in orthodontic applications and to determine corrosion behaviour with classical experimental design methods. [ABSTRACT FROM AUTHOR]

Successful joining of dissimilar materials is important in order to optimize mechanical properties such as strength, density, corrosion resistance, etc., for several applications. Al-alloys, particularly hardenable ones, are widely utilized in automobile and aerospace industries owing to their excellent properties. Besides all Al-alloys are light-weight they exhibit different properties. For instance, AA6061 alloy display excellent corrosion resistance whereas alloy AA7075 possesses a very high strength. Thus, it is worth to search the joinability of dissimilar Al-alloys plates and their performances. In this study, dissimilar Al-alloys joints (AA6061-O/AA7075-O and AA6061-T6/AA7075-T6) were produced using friction stir welding, which is well demonstrated to produce reliable joints in similar Al-alloy plates, employing two different sets of weld parameters. Detailed metallography, micro hardness measurements and tensile testing were conducted in order to characterize the joints obtained and to determine the effect of temper condition on joint performance. [ABSTRACT FROM AUTHOR]

Heat treatable, high strength, weldable 7020-T651 alloy is used due to its high fatigue strength and high yield strength in welded military structures. This alloy has satisfactory arc weldability with filler metal 5356 and after welding, mechanical properties equivalent to those of the parent metal in the T4 temper can be achieved. However, it shows a strong sensitivity to exfoliation corrosion in the heat affected zone, on either side of the welding bead once it has been incorporated into a welded structure. In order to successfully use this material in welded design suitable precaution must be taken against exfoliation corrosion. Step aging after welding will provide an appreciable measure of protection against exfoliation corrosion [1,2]. It is the aim of this study to see the effect of heat treatment after welding, on exfoliation corrosion resistance and mechanical strength of EN AW 7020-T651 aluminium alloy. [ABSTRACT FROM AUTHOR]

Duplex Stainless Steels offer good combination of strength and corrosion resistance compared to austenitic stainless steels, and become an alternative in many application fields, such as chemical, oil, and gas industries like pipelines and reaction vessels. The mechanical properties and service life ofDSS are strongly dependent on the ferrite and austenite ratio and the formation of secondary phases and precipitates during heating and cooling periods. In the present study, solidification and low temperature phase transformations during single and multi pass welding via Hybrid plasma arc (HPA) and gas metal arc (GMA) welding techniques. Depending on differences in the microstructure of the weld metal, mechanical behaviour changes were discussed. [ABSTRACT FROM AUTHOR]

In this study AA2024 alloy, which is used especially in aircraft body, wings and automotive industry due to its lightness, workable aspect, high corrosion resistance and durability, was welded with stir friction method, and fatigue, hardness, bending and tension experiments of the joints obtained were conducted. Welding progress speed of the 4 mm thick sheets and stir tool rotation were determined to be the variable parameters. These parameters were taken as 20 mm shoulder width, 1000 rpm traverse speed, 1500 rpm, 2500 rpm and the progress speed was taken as 120 mm/min and 200 mm/min. [ABSTRACT FROM AUTHOR]

The extent of this work is operating characteristics of a horizontal shafted centrifugal pump (which has stainless steel wheel) which has been operated for 7 hours on the average. A closed circuit pump system (circulating within itself) which was formed by attaching a horizontal shafted centrifugal pump which can be used in irrigation applications with a drum has been operated for 150 hours at laboratory conditions. To define the operating properties of the pump, its operating characteristics were measured in respect to ISO 2548. Furthermore, observations have been done to determine whether there is a connection between operating characteristics of the pump and the wear and corrosion occurred on the wheel or not. [ABSTRACT FROM AUTHOR]