Rubber has become an indispensable material for the technological development of civilization, including simple balloon and complex rocket propellant. Rubber Industry worldwide is using on an average 50% of raw materials. These materials were mostly petroleum-based, except natural rubber (NR), steel cord and bead wire. Using of these petroleum-based raw materials not only depletes natural resources, but also produces more extreme environmental hazards. The waste tire rubber problem is of great magnitude and has far reaching environmental and economic implications. There are some ways for recycling of rubber, such as reclaiming technology, surface treatment, grinding and pulverization technology, devulcanization technology. Methods of devulcanizing rubber (or elastomers) have been researched almost since the time of the discovery of the rubber/sulfur vulcanization process. By devulcanization process the cross-links in the structure of rubber are broken and devulcanized rubber can be revulcanized into a raw material for rubber industry, which is a highly valued form of waste rubber. This study provides a review of the recent advances in understanding of methods of recycling rubber and claims that the capacity of thermomechanical and mechanochemical devulcanization methods of recycling waste tire rubber can be improved in future studies.

The corrosion resistance properties of two ultra-high strength steels, Docol 1200 and 1400 were studied in 3.5 wt% NaCl solution using chemical and electrochemical techniques supported by surface characterization techniques namely scanning electron microscope (SEM), energy dispersive spectroscopy (EDX), atomic force microscope (AFM), and optical profilometer. The mechanical properties of both Docol 1200 and Docol 1400 uncorroded and corroded were determined by tensile test. Results obtained reveal that the two alloys exhibit similar mechanical properties. Corrosion has effect on the mechanical properties of the alloys. Corrosion studies reveal that both Docol 1200 and 1400 are prone to corrosion in NaCl environment. A corrosion rate of 30.6 mpy and 49.6 mpy was recorded for a Docol 1200 at 25 °C and 60 °C, respectively. For Docol 1400, the corrosion rate obtained at 25 °C and 60 °C was 32.7 mpy and 52.4 mpy, respectively. Docol 1200 is adjudged to exhibit superior corrosion resistance property than Docol 1400. The optical profilometric results disclose that Docol 1200 and Docol 1400 suffered pitting corrosion in NaCl solution. Pitting corrosion was more severe with Docol 1400 than 1200.

Prototype parts can be produced rapidly and at low cost using the incremental forming method. The most important problem with this method is that it causes undesirable variations in wall thickness. Various methods have been developed to improve the wall thickness distribution of the part resulting from forming. One of these techniques, the rolling blank holder (TPIF-RL) method, was used in this study to form 1 mm-thick HC380LA sheet. The Taguchi experimental design was used to determine optimum levels of each of the parameters (forming force, surface roughness and wall thickness) separately via signal/noise analysis. Gray Relational Analysis was then performed to determine the parameters that optimize surface roughness and wall thickness together. In the study, it was determined that the use of low pressing force increases the wall thickness. As a result, a 6% increase in wall thickness was achieved by using the optimum parameters.

Background : Treatment with anticholinergic agents is the mainstay of therapy for detrusor instability (DI), a chronic and morbid condition characterized by urge urinary incontinence. The aim of this study is to assess the effectiveness and tolerability of tolterodine and oxybutynin in children with DI. Methods : A total of 60 children with DI were enrolled, 30 (14 male, 16 female, mean age 7.97 ± 2.71 years) in the tolterodine group and 30 (12 male, 18 female, mean age 7.33 ± 2.23 years) in the oxybutynin group. In this prospective study we reviewed data from 60 children followed for at least 6 months. All of the patients in the study population had a history of dysfunctional voiding. Urodynamic investigations were conducted in all of the patients before and after anticholinergic treatment. Episodes of urge urinary incontinence and adverse events were also evaluated. Results : Improvements in urge incontinence episodes were similar for the children who received tolterodine or oxybutynin. Improvements in the urodynamic parameters were also the same in the two groups. Adverse events were significantly lower in the tolterodine group (13 events in 13 patients) compared to the oxybutynin group (27 events in 20 patients; P = 0.027). Conclusion : Reductions in urge urinary incontinence episodes were similar with tolterodine and oxybutynin in children with DI. Side-effects were more common with oxybutynin. Treatment of children with DI with tolterodine shows significantly better tolerability and this may enhance children's compliance during long-term treatment.

The use of high-strength sheet material applications in the automotive industry has become widespread due to their high strength/weight ratios. The formability, however, of these high-strength sheet materials is limited at room temperatures (RTs). In this study, the first of its kind to be conducted, experimental research was performed on the formability of HC420LA grade sheet material using the warm deep drawing (WDD) method. Temperature control is the most important parameter in WDD. In this method, a new temperature control system was designed and manufactured to increase the formability of HC420LA grade sheet material. The limiting drawing ratio (LDR) for a 1.2-mm sheet thickness of HC420LA grade sheet material, which is 2.14 at RT, increased to 2.47 after applying this method. For a 1.5-mm sheet thickness of HC420LA, LDR, which is 2.15 at RT, increased to 2.59 after applying this method. Percent increases of the drawing ratios for 1.2 and 1.5 mm thicknesses were 15.42 and 20.45 %, respectively. A maximum reduction of 15 % in thickness was obtained in formed cups. Lastly, the microstructures of the warm cup's punch corner region and wall and bottom regions were investigated under an optical microscope. The results showed whether any changes occurred in the microstructures and mechanical properties.

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In this study, the effects of local heat treatment temperature on the V-bending formability of Martensitic 1200 steel, was investigated experimentally. In the first stage of the study, local heating temperatures were determined according to the stress-strain curves obtained as a result of the hot tensile test. Other experimental parameters included temperature (room temperature -RT/25, 300, 400 and 500°C), die-punch angle (30, 60, 90 and 120°) and punch holding time (0 and 10 s). The heating procedure in the bending operation was carried out locally only in the bending zone with the temperature controlled heating rod. The hardness values were found as 5.19% HV at the forming temperatures of RT-300°C, 2.31% HV at 300-400°C and 1.85% HV at 400-500°C. Due to the coarseness of the carbides in the microstructure, softening of the sheet material was observed up to 400°C. The slight increase in the flexure observed in the sheet materials bent at 500°C was caused by secondary precipitation hardening.

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