Cold spray is a process which is used in coating industry and manufacturing of new parts. Experimental studies of this process are expensive and also very difficult due to high velocity of particles. Therefore, one effective method to study this process is its computer simulation. Previous works show that the Johnson-Cook hardening law has been usually used for simulation of this process. However, it is unanimously believed that this model is not able to reproduce the material behavior at extremely high strain rates commonly occurred in the Cold spray process. Therefore, the simulation results are expected to improve if a suitable material model for extremely high strain rates is used. In this study, the PTW1 model was implemented in ABAQUS commercial finite element package. The Cold spray process was then simulated for copper using both the PTW and Johnson-Cook hardening models. A comparison between the simulation and experimental results showed that the PTW model did improve the simulation results. The predicted flow stress by Johnson-Cook model was also shown to be not so sensitive to strain rate at extremely high strain rates.

Background and Aim: Postural control is the base of body movements and is required for most daily and sports activities. Several factors can affect the performance of postural control system and reduce postural stability. According to the previous studies, the Cold is one of the factors that can influence the neuromuscular system and thus increase postural sway. Therefore, the present study was conducted to assess the postural sway of college soccer players following a protocol of local Cold application by Cold spray at ankle joint.Materials and MethodIn the present quasi-experimental study, 30 male college soccer players were purposefully selected with a mean age of 23.2 ± 1.29 years, mean weight of 69.5 ± 6.73 kg, and mean height of 177.11 ± 5.92 cm. Postural sway characteristics of the participants were measured by the pressure distribution detecting device and the data was recorded as pre-test scores. Next, the Cold spray was simultaneously applied on both medial and lateral aspects of the ankle joint of the dominant leg. Immediately then, the postural sway characteristics were measured again and the data was recorded as post-test scores. T-test was used to compare the means.Results: The results showed that despite the relative increase in postural sway characteristics of the participants after using the Cold spray, there was no significant difference between these characteristics before and after cryotherapy.Conclusion: It seems that using Cold spray for local cooling of ankle joint has no significant effect on the postural sway in college soccer players. Nonetheless, because of the slight increase in postural sway characteristics after cryotherapy, the results of the study should be interpreted with caution.

Introduction: Now a day, there is a crucial need for a quick and effective disinfectant to prevent nosocomial infections in hospitals. Meanwhile evaluation and validation of disinfectants are important. hospital surfaces, instruments, and rooms. the aim of this study was to evaluate the effect, quality and disinfectant activity of the Quick spray (Virobac spray). Materials and Methods: Antibacterial activity of Quick spray (Virobac spray) was evaluated on four different gram-positive and gram-negative bacterial strain including Staphylococcus aureus (ATCC 29737), Pseudomonas aeruginosa (ATCC 28753), Escherichia coli (ATCC 25922) and Enterococcus faecalis (ATCC 1237. The antimicrobial solution was examined in ½ , ¼ , and 1/8 dilutions, and the antibacterial effect was determined after the exposure time such as 45, 60, 90, and 120 seconds. Results: Quick spray (Virobac spray) show a powerful antibacterial activity even in ½ dilution, also we demonstrate that the antibacterial activity of this solution will be enhanced with increased time of exposure. Conclusion: the result of this study demonstrated that Quick spray (Virobac spray) is a broad-spectrum and effective disinfectant and are able to inhibit the growth of a wide range of bacteria including grampositive and gram-negative bacteria.

Cold spray (CS) with Metal matrix composite (MMC) is an alternative process for improving surface properties, which is crucial in plastic manufacturing. Understanding of particle behavior during impact is required for CS. This study focused on developing a simplified computational framework using the single-shot particle impact model to predict the adherence of matrix particles in the low-velocity impact. In this work, the hardened SKD11 coated with Al matrix/TiN reinforcement composite was selected, aiming to verify the proposed framework. Al particle impact at different temperatures (300K, 623K, and 723K) under the low-velocity range of 350–600 m/s were simulated, revealing the particle temperature affects the cohesive area. As the particle temperature increases, the areas also increase under similar velocity. The flattening ratio was calculated from the simulation and found to be influenced by the particle velocity. The CS of pure Al and Al/TiN (75:25 wt.%) on the hardened SKD11 under 623K and 723K was carried out under the experiment with the estimated pressure based on the flattening ratio and particle behavior. The results suggest the coatings could be developed using estimated pressure. Al/TiN coating was deposited at different initial particle temperatures. Results reveal that low coating porosity (<0.01%) could be obtained for both cases, and the higher particle temperature reveals higher thickness and %porosity, which agree well with the computational results. The developed framework shows high potential for designing CS for MMC coating, provided the reinforcement particles do not significantly affect the matrix particle flow or impact conditions.

Offering deposition of dense coating at solid state, Cold spray consolidating method can be used for deposition of a wide variety of composite coatings including metal-matrix composite coatings. In this research, deposition of Ni-Ti composite coating using Cold spraying and formation of intermetallics after post spray heat-treatment were investigated. Ni and Ti powders were physically blended with equivalent volume ratio (68. 3% at. Ni-31. 7%at. Ti), sprayed as the feedstock powder and composite coating with 35. 2 at. % Ni-64. 8 at. % Ti composition was obtained. Post heat-treatments were conducted at 740 ̊ C, 900 ̊ C, and two-step heat-treatment 740 ̊ C and 960 ̊ C for different times. Microstructural investigation showed that all three equilibrium intermetallics of binary Ni-Ti phase diagram including Ni3Ti, Ti2Ni and NiTi phases were formed at all heat-treatment experiments and fraction of Ni3Ti phase decreased with consumption of the Ni precursor. Additionally, it was found that Cold sprayed composite coatings had fast intermetallics formation and growth kinetics compared with those of common press and sinter samples which was addressed through deformation enhanced interdiffusion and particle/particle bonding of Cold sprayed coatings.