in this study, friction stir spot welding (fssw) is applied to join the tial6v4 titanium alloy with 1.5 mm thickness and then the effect of rotational speed and tool dwell time on microstructure and mechanical properties is investigated. in this regard, the speed of the tool rotation was considered as 800, 1000, and 1200 rpm, as well as the tool dwell time was set at 7 and 12s. microstructural ...

in this research, the compositing of the surface of az31b magnesium alloy with cnt was studied by fsp. the parameters under study were rotational speed (500-1500 rpm), transverse speed (12-44 mm/min), number of passes (1-4), and cnt weight fraction (0-2%). microhardness testing, optical metallography, fesem, and eds analysis were employed for the characterization of the samples. the suitable li...

introduction recently, employment of rotary tillers has been expanded in gardens and small farms, especially in the northern of iran. however using the l-shaped blades in the conventional rotary tillers have some problems such as severe vibration problems, weeds stucking around the blades, forming the plow pan and lower performance due to the less powers of such small rototillers. therefore in ...

due to climate changes in recent years, in order to attain comfort and convenience, demands for heating, ventilating, and air conditioning (hvac) systems have been increased around the world, which has led to increases in emissions and power. desiccant cooling systems (dcss) are designed and built to reduce moisture and power consumption, create comfortable conditions for people in a building, ...

paddy de-awning using a de-awner increases the uniformity and flow rate of paddy grains through the orifices of hoppers, bucket elevators and chutes. in this study the effects of paddy variety, rotational blade speed and moisture content on performance of a prototype de-awner machine were investigated. the experiment was conducted in a factorial design with three factors, variety (hashemi and b...

The basic aim of present study is to examine the effect of main friction stir welding (FSW) parameters on the quality of AA 6063 plate welds. Welding of AA6063 was carried out by a vertical milling machine, using different tools with a stationary shoulder and during the welding no external heating system was used. Different welding parameters studied were the tool rotational speed which varied ...

in this work, improved heat generation models are developed for straight and tapered shoulder geometries with different tool pin profiles in friction stir welding. the models are developed considering the welding process as a combination of the pure sliding and the pure sticking conditions. from the results, the amount of heat generation is directly proportional to the number of edges in the pi...

Laminar mixing of glycerin in a chaotic mixer is carried by means of the blob deformation method. The mixer was a cylindrical vessel with two rotational blades which move along two different circular paths with a stepwise motion protocol. The flow visualization was performed by marking of the free surface of the flow with a tracer. The effects of controlling parameters such as rotational speed ...

organic manure plays an important role in the improvement of soil structure by decreasing bulk density and increasing porosity. however, the method of manure spreading influences its beneficial impact on soil structure. in this study, a novel helical manure distributor machine capable of spreading manure with different moisture contents at maximum distribution width was developed and the machin...