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In this research, the effect of experimental applications by using robotics technology in Science and Technology course the "Force and Motion" unit on the level of scientific creativity and scientific attitude of students was investigated. This research was designed according to the quasi-experimental method pre-test post-test design with a control group. In the research that was carried out with the 7 th grade students (N=40) studying at a secondary school in Kayseri Province, Turkey. "Scientific Creativity Test" and "Scientific Attitude Scale" were used as data collection tools. At the end of implementation which lasted eight weeks, the quantitative data obtained were evaluated at 0.05 meaningfulness level through SPSS package software. "Mann Whitney U-Test" and "Wilcoxon Signed Ranks Test" were applied as analysis techniques. As a result of the research, while a meaningful difference was found between scientific creativity and scientific attitude pre-test post-test points of the students in the experimental group which robotics technology was used, no difference was found in the control group. Thus, it was found out that robotics developed scientific creativity and scientific attitude level of the students who joined the research by affecting it positively. Therefore, it is recommended that robotics-assisted science laboratory activities should also be planned and implemented in different classes, units or subjects to provide a science teaching with a better quality that supports and improves scientific creativity and scientific attitudes of students.

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The effect of Si content (0.5, 1.5, and 5 wt.%) and growth velocity on the microstructure, microhardness, ultimate tensile strength, electrical resistivity, enthalpy, and specific heat properties of the directionally solidified Al-Mn eutectic alloy have been investigated. Al-1.94Mn-xSi (x = 0.5, 1.5, 5 wt.%) samples were prepared from pure metals (99.99 % purity) under the vacuum. These alloys were directionally solidified under constant temperature gradient G (4.9 K mm −1) and different growth velocities V (from 8.3 to 978 µm s −1) in a Bridgman-type growth apparatus. Measurements of primary dendrite arm spacing (λ), microhardness (HV), ultimate tensile strength (UTS) and electrical resistivity (ρ) of the samples were carried out and then expressed as functions of growth velocity and Si content (Co). Additionally, the enthalpy of fusion (ΔH) and specific heat capacity (Cp) for the same alloys were determined by a differential scanning calorimeter (DSC) from the heating curves. It has been found that the values of HV, UTS, and ρ increase with increasing values of V and Co. On the contrary, the values of λ decrease with increasing V. The increasing Si content in Al-Mn leads to a decrease of ΔH and Cp.

A bstractIn the present work, the effect o f growth rate and temperature gradient on microstructure and mechanical properties o f eutectic alloy has been investigated. Alloys prepared under steady-state conditions by vacuumed hot filing furnace. Then, the alloys were directionally solidified upward with different growth rates (V= 11.62-230.77 pm/s) at a constant temperature gradient (G=7.17 K/mm) and with different temperature gradients (G=7.17-11.04 K/mm) at a constant growth rate (V= 11.62 pm/s) by a Bridgman furnace. The microstructures were observed to be lamellae ofZn, Al and broken lamellae CuZn4 phases from quenched samples. The values o f eutectic spacing, microhardness and ultimate tensile strength o f alloys were measured. The dependency o f the microstructure and mechanical properties on growth rate and temperature gradient were investigated using regression analysis.